共用题干Rainmaking1 The idea of rainmaking is almost as old as man,but it was not until 1946 that man succeeded in making rain.In ancient times,rainmakers had claimed to bring rain by many methods:dancing,singing,killing animals(including humans).2 For a long time,men have understood where rain comes from.Water from the surface of oceans and lakes becomes part of the air,where it forms clouds from which rain falls.But exactly what starts the forma- tion of raindrops was not known until quite recently.A man named John Aitken proved that drops of water gather around tiny bits of dust or other matter. The centers of the drops are so small that the human eye can- not see them.Without such centers,it seems raindrops do not form.3 During World War Ⅱ,Dr. Irving Langmir,and his assistant Schaefer,were hired by the General Electric Company to study how and why ice forms on the wings of airplanes.They went to a mountain in New Hampshire,where snowstorms are common and cold winds blow. They were surprised to find that often the temperature of the clouds surrounding them was far below the freezing point,and yet ice did not form in the clouds.4 After the War,Schaefer experimented with a machine that created cold,moist air similar to the air found in clouds.To imitate the moist air of a cloud.Schaefer would breathe into the machine.Then he would drop into the freezer a bit of powder,sugar,or some other substance.For weeks and months he tried everything he could imagine.Nothing happened.No crystals of ice were formed.None of the substances would serve as the center of a snow crystal or raindrops.5 One July morning,Schaefer was dropping in bits of various substances and watching the unsuccessful results.Finally,a friend suggested that they go to eat lunch and Schaefer went with him.As usual,he left the cover of the freezer up,since cold air sinks and would not escape from the box.6 Returning from lunch,Schaefer found that the temperature of the freezer had risen to a point higher than that required for ice crystals to remain solid.There were two choices now.He could close the cover and wait for the freezer itself to lower the air temperature,or he could make the process occur faster by adding dry ice a gas in solid form that is very,very cold.He chose the latter plan.As he dropped the steaming white dry ice into the freezer,he happened to breathe out a large amount of air. And there,before his eyes,it happened ! He had made ice crystals,not by adding centers to the moisture,but by cooling the breath so much that the liquid had to form crystals!Then he began to blow his breath into the freezer and drop large pieces of dry ice through it to create crystals which became a tiny snowstorm falling slowly to the floor of his laboratory.7 After planning carefully,Schaefer made an experiment by dropping dry ice from his plane to the clouds below him.As was expected,snow formed and fell from the bottom of the cloud.Schaefer succeeded. He made history.Schaefer found a way of how to make ice crystals_________.A:imaginativelyB:recentlyC:carefullyD:unscientificallyE:accidentallyF:satisfactorily

共用题干
Rainmaking

1 The idea of rainmaking is almost as old as man,but it was not until 1946 that man succeeded in
making rain.In ancient times,rainmakers had claimed to bring rain by many methods:dancing,singing,
killing animals(including humans).
2 For a long time,men have understood where rain comes from.Water from the surface of oceans and
lakes becomes part of the air,where it forms clouds from which rain falls.But exactly what starts the forma-
tion of raindrops was not known until quite recently.A man named John Aitken proved that drops of water
gather around tiny bits of dust or other matter. The centers of the drops are so small that the human eye can-
not see them.Without such centers,it seems raindrops do not form.
3 During World War Ⅱ,Dr. Irving Langmir,and his assistant Schaefer,were hired by the General
Electric Company to study how and why ice forms on the wings of airplanes.They went to a mountain in New
Hampshire,where snowstorms are common and cold winds blow. They were surprised to find that often the
temperature of the clouds surrounding them was far below the freezing point,and yet ice did not form in the
clouds.
4 After the War,Schaefer experimented with a machine that created cold,moist air similar to the air
found in clouds.To imitate the moist air of a cloud.Schaefer would breathe into the machine.Then he
would drop into the freezer a bit of powder,sugar,or some other substance.For weeks and months he tried
everything he could imagine.Nothing happened.No crystals of ice were formed.None of the substances
would serve as the center of a snow crystal or raindrops.
5 One July morning,Schaefer was dropping in bits of various substances and watching the unsuccessful
results.Finally,a friend suggested that they go to eat lunch and Schaefer went with him.As usual,he left
the cover of the freezer up,since cold air sinks and would not escape from the box.
6 Returning from lunch,Schaefer found that the temperature of the freezer had risen to a point higher
than that required for ice crystals to remain solid.There were two choices now.He could close the cover and
wait for the freezer itself to lower the air temperature,or he could make the process occur faster by adding dry
ice a gas in solid form that is very,very cold.He chose the latter plan.As he dropped the steaming white
dry ice into the freezer,he happened to breathe out a large amount of air. And there,before his eyes,it
happened ! He had made ice crystals,not by adding centers to the moisture,but by cooling the breath so
much that the liquid had to form crystals!Then he began to blow his breath into the freezer and drop large
pieces of dry ice through it to create crystals which became a tiny snowstorm falling slowly to the floor of his
laboratory.
7 After planning carefully,Schaefer made an experiment by dropping dry ice from his plane to the
clouds below him.As was expected,snow formed and fell from the bottom of the cloud.Schaefer succeeded.
He made history.

Schaefer found a way of how to make ice crystals_________.
A:imaginatively
B:recently
C:carefully
D:unscientifically
E:accidentally
F:satisfactorily

参考解析

解析:本段简略地叙述了雨水的来源和形成雨滴的核心部分。
本段介绍了Langmir和Schaefer受雇于通用电气公司(General Electric Company),研究 机翼结冰的成因。
本段描述了Schaefer从事的人工制造冰晶体的实验,但没有成功。
由文章第六段“As he dropped the steaming white dry ice into the freezer, he happened to breathe out。large amount of air",可知一次偶然的机会,Schaefer在投人干冰的时候,呼出一大 口气,结果冰晶体却出现了。他在无意中发现了制造冰晶体的方法。
在文章第一段中提到“In ancient times, rainmakers had claimed to bring rain by many methods: dancing, singing, killing animals (including humans)"。该句中提到的作为造雨、求雨 的手段的dancing, singing, killing animals (including humans)等都是不科学的方法。
答题的解释请参阅第26题的说明。
由文章第七段“After planning carefully, Schaefer made an experiment by dropping dry ice from his plane to the clouds below him.As was expected,snow formed and fell from the bottom of the cloud.Schaefer succeeded",可知选C。
由文章第二段“But exactly what starts the formation of raindrops was not known until quite recently",可知选B。第4部分:阅读理解第一篇 本篇文章主要讲述了食用土豆对人体免疫系统的益处。

相关考题:

阅读理解There is no doubt that man is a member of the animal kingdom.Anyone who has thought about this fact seriously must have wondered how it has come about that man has achieved a position so supreme(最高的) among the myriad(无数的) kinds of animal life.Two characteristics of man, in comparison with all other animals, that stand out above all others are the creation and use of tools and the development and use of language.Since no other animals have achieved these abilities, it must be assumed that man’s evolutionary development led to his capacity to create and use tools and to devise and use language.Once these abilities and practices evolved, they probably became driving forces in the further evolution of man.Those members of the species who become most proficient(精通的) in the fabrication of tools and in the command of language and thought would tend to survive and maintain their kind for good, at the expense of those of lesser ability.11.Which of the following statements best expresses the main idea of the passage?()A.Tools and language are either the effects or the causes of human evolution.B.No other animals have achieved human abilities.C.Among the animals, only man is able to use tools and language.D.Man owns his capacity to making use of tools and language.12.“Animal kingdom” in the passage refers to ().A.the place where all animals liveB.the animal societyC.all kinds of animals, including manD.the forest with animals13.One important condition for man’s evolution is() .A.the animal kingdomB.a supreme positionC.the myriad kindsD.his natural capacity14.The phrase “come about” in the passage is likely to mean ________.A.happenedB.appearedC.arrivedD.succeeded15.The last sentence suggests that() .A.those of lesser ability would be very expensiveB.in order to survive, man has to sacrifice some other animalsC.those who become proficient in making tools can speak wellD.language and thought could be acquired by man

Once upon a time there was ( ) old man who had ( ) four-year-old grandson. A、the/ theB、an/ anC、an/ aD、A/ a

共用题干Old Man Myths and Realities1 When does a middle-aged man become an old man?Officially,of course,it's when we reach retirement age. But, as we all know, this is a fairly blunt(生硬的)method of decision making. As life expectancy(预期寿命)increases, retirement planning needs to be changed .This is because being an old man today is very different from what it was a generation or so ago.2 Sixty-five is the new middle-aged man. These days people are talking about the young-old,that is ages 70-75,and those over 75 as the old-old. The young-old frequently continue in good health and maintain strong links with friends and family.The old-old have a much higher chance of poor health and social isolation.3 Although men are living longer,there are still more old women than old men.This fact alone should arouse interest as to why.Relatively little is actually known about why this is the case or about the experiences of the old man .Sure,we are aware that the old man experiences anxiety,financial problems,loneliness,etc.,but that's really about all we know.4 It is usually believed that the old man often complains about their health.In fact,most rate their health as good even though most are diagnosed with at least one chronic illness. The physical health of the old man is strongly affected by their health behavior when they were younger. Nowadays men generally live longer than_________.A: in good healthB: in the pastC: in the wrongD: the old manE: a middle-aged manF: a young man

共用题干Old Man Myths and Realities1 When does a middle-aged man become an old man?Officially,of course,it's when we reach retirement age. But, as we all know, this is a fairly blunt(生硬的)method of decision making. As life expectancy(预期寿命)increases, retirement planning needs to be changed .This is because being an old man today is very different from what it was a generation or so ago.2 Sixty-five is the new middle-aged man. These days people are talking about the young-old,that is ages 70-75,and those over 75 as the old-old. The young-old frequently continue in good health and maintain strong links with friends and family.The old-old have a much higher chance of poor health and social isolation.3 Although men are living longer,there are still more old women than old men.This fact alone should arouse interest as to why.Relatively little is actually known about why this is the case or about the experiences of the old man .Sure,we are aware that the old man experiences anxiety,financial problems,loneliness,etc.,but that's really about all we know.4 It is usually believed that the old man often complains about their health.In fact,most rate their health as good even though most are diagnosed with at least one chronic illness. The physical health of the old man is strongly affected by their health behavior when they were younger. Paragraph 2__________A:New definitions of the old manB:Changing concept of the old manC:Health of the old man D:Happy old man and sad old man E:Limited knowledge of the old man's experiencesF:Contempt for the old man

共用题干Old Man Myths and Realities1 When does a middle-aged man become an old man?Officially,of course,it's when we reach retirement age. But, as we all know, this is a fairly blunt(生硬的)method of decision making. As life expectancy(预期寿命)increases, retirement planning needs to be changed .This is because being an old man today is very different from what it was a generation or so ago.2 Sixty-five is the new middle-aged man. These days people are talking about the young-old,that is ages 70-75,and those over 75 as the old-old. The young-old frequently continue in good health and maintain strong links with friends and family.The old-old have a much higher chance of poor health and social isolation.3 Although men are living longer,there are still more old women than old men.This fact alone should arouse interest as to why.Relatively little is actually known about why this is the case or about the experiences of the old man .Sure,we are aware that the old man experiences anxiety,financial problems,loneliness,etc.,but that's really about all we know.4 It is usually believed that the old man often complains about their health.In fact,most rate their health as good even though most are diagnosed with at least one chronic illness. The physical health of the old man is strongly affected by their health behavior when they were younger. Paragraph 4__________A:New definitions of the old manB:Changing concept of the old manC:Health of the old man D:Happy old man and sad old man E:Limited knowledge of the old man's experiencesF:Contempt for the old man

共用题干Old Man Myths and Realities1 When does a middle-aged man become an old man?Officially,of course,it's when we reach retirement age. But, as we all know, this is a fairly blunt(生硬的)method of decision making. As life expectancy(预期寿命)increases, retirement planning needs to be changed .This is because being an old man today is very different from what it was a generation or so ago.2 Sixty-five is the new middle-aged man. These days people are talking about the young-old,that is ages 70-75,and those over 75 as the old-old. The young-old frequently continue in good health and maintain strong links with friends and family.The old-old have a much higher chance of poor health and social isolation.3 Although men are living longer,there are still more old women than old men.This fact alone should arouse interest as to why.Relatively little is actually known about why this is the case or about the experiences of the old man .Sure,we are aware that the old man experiences anxiety,financial problems,loneliness,etc.,but that's really about all we know.4 It is usually believed that the old man often complains about their health.In fact,most rate their health as good even though most are diagnosed with at least one chronic illness. The physical health of the old man is strongly affected by their health behavior when they were younger. Most old men consider themselves to be__________.A: in good healthB: in the pastC: in the wrongD: the old manE: a middle-aged manF: a young man

共用题干Old Man Myths and Realities1 When does a middle-aged man become an old man?Officially,of course,it's when we reach retirement age. But, as we all know, this is a fairly blunt(生硬的)method of decision making. As life expectancy(预期寿命)increases, retirement planning needs to be changed .This is because being an old man today is very different from what it was a generation or so ago.2 Sixty-five is the new middle-aged man. These days people are talking about the young-old,that is ages 70-75,and those over 75 as the old-old. The young-old frequently continue in good health and maintain strong links with friends and family.The old-old have a much higher chance of poor health and social isolation.3 Although men are living longer,there are still more old women than old men.This fact alone should arouse interest as to why.Relatively little is actually known about why this is the case or about the experiences of the old man .Sure,we are aware that the old man experiences anxiety,financial problems,loneliness,etc.,but that's really about all we know.4 It is usually believed that the old man often complains about their health.In fact,most rate their health as good even though most are diagnosed with at least one chronic illness. The physical health of the old man is strongly affected by their health behavior when they were younger.A man in his mid-60s is now regarded as________.A: in good healthB: in the pastC: in the wrongD: the old manE: a middle-aged manF: a young man

Only when he was told that his precious stone was but an artificial gem did the old man realize that he had been cheated of almost RMB 100,000 yuan.A: superficial B: custom-made C: ready-made D: man-made

共用题干Rainmaking1 The idea of rainmaking is almost as old as man,but it was not until 1946 that man succeeded in making rain.In ancient times,rainmakers had claimed to bring rain by many methods:dancing.singing-Kiiiing animals t including humans).2 For a long time,men have understood where rain comes from.Water from the surface of oceans and lakes becomes part of the air,where it forms clouds from which rain falls.But exactly what starts the formation of raindrops was not known until quite recently.A man named John Aitken proved that drops of water gather around tiny bits of dust or other matter.The centers of the drops are so small that the human eye cannot see them.Without such centers,it seems raindrops do not form.3 During World War Ⅱ,Dr.Irving Langmir,and his assistant Schaefer,were hired by the General Electric Company to study how and why ice forms on the wings of airplanes.They went to a mountain in New Hampshire,where snowstorms are common and cold winds blow.They were surprised to find that often the temperature of the clouds surrounding them was far below the freezing point,and yet ice did not form in the clouds.4 After the War,Schaefer experimented with a machine that created cold,moist air similar to the air found in clouds.To imitate the moist air of a cloud,Schaefer would breathe into the machine.Then he would drop into the freezer a bit of powder,sugar,or some other substance.For weeks and months he tried everything he could imagine.Nothing happened.No crystals of ice were formed.None of the substances would serve as the center of a snow crystal or raindrops.5 One July morning,Schaefer was dropping in bits of various substances and watching the unsuccessful results.Finally,a friend suggested that they go to eat lunch and Schaefer went with him.As usual,he left the cover of the freezer up,since cold air sinks and would not escape from the box.6 Returning from lunch,Schaefer found that the temperature of the freezer had risen to a point higher than that required for ice crystals to remain solid.There were two choices now.He could close the cover and wait for the freezer itself to lower the air temperature,or he could make the process occur faster by adding dry ice-a gas in solid form that is very,very cold.He chose the latter plan.As he dropped the steaming white dry ice into the freezer,he happened to breathe out a large amount of air.And there,before his eyes,it happened!He had made ice crystals,not by adding centers to the moisture,but by cooling the breath so much that the liquid had to form crystals!Then he began to blow his breath into the freezer and drop large pieces of dry ice through it to create crystals which became a tiny snowstorm falling slowly to the floor of his laboratory.7 After planning carefully,Schaefer made an experiment by dropping dry ice from his plane to the clouds below him.As was expected,snow formed and fell from the bottom of the cloud.Schaefer succeeded.He made history.Paragraph 2______A:Langmir and Schaefer's Work for the GE CompanyB:Langmir and Schaefer's Discovery of Rain-formingC:Men's Knowledge of Rain-formingD:Schaefer's Several Unsuccessful ExperimentsE:Schaefer's Discovery by AccidentF:Langmir and Schaefer's Successful Cooneration

共用题干Rainmaking1 The idea of rainmaking is almost as old as man,but it was not until 1946 that man succeeded in making rain.In ancient times,rainmakers had claimed to bring rain by many methods:dancing,singing,killing animals(including humans).2 For a long time,men have understood where rain comes from.Water from the surface of oceans and lakes becomes part of the air,where it forms clouds from which rain falls.But exactly what starts the forma- tion of raindrops was not known until quite recently.A man named John Aitken proved that drops of water gather around tiny bits of dust or other matter. The centers of the drops are so small that the human eye can- not see them.Without such centers,it seems raindrops do not form.3 During World War Ⅱ,Dr. Irving Langmir,and his assistant Schaefer,were hired by the General Electric Company to study how and why ice forms on the wings of airplanes.They went to a mountain in New Hampshire,where snowstorms are common and cold winds blow. They were surprised to find that often the temperature of the clouds surrounding them was far below the freezing point,and yet ice did not form in the clouds.4 After the War,Schaefer experimented with a machine that created cold,moist air similar to the air found in clouds.To imitate the moist air of a cloud.Schaefer would breathe into the machine.Then he would drop into the freezer a bit of powder,sugar,or some other substance.For weeks and months he tried everything he could imagine.Nothing happened.No crystals of ice were formed.None of the substances would serve as the center of a snow crystal or raindrops.5 One July morning,Schaefer was dropping in bits of various substances and watching the unsuccessful results.Finally,a friend suggested that they go to eat lunch and Schaefer went with him.As usual,he left the cover of the freezer up,since cold air sinks and would not escape from the box.6 Returning from lunch,Schaefer found that the temperature of the freezer had risen to a point higher than that required for ice crystals to remain solid.There were two choices now.He could close the cover and wait for the freezer itself to lower the air temperature,or he could make the process occur faster by adding dry ice a gas in solid form that is very,very cold.He chose the latter plan.As he dropped the steaming white dry ice into the freezer,he happened to breathe out a large amount of air. And there,before his eyes,it happened ! He had made ice crystals,not by adding centers to the moisture,but by cooling the breath so much that the liquid had to form crystals!Then he began to blow his breath into the freezer and drop large pieces of dry ice through it to create crystals which became a tiny snowstorm falling slowly to the floor of his laboratory.7 After planning carefully,Schaefer made an experiment by dropping dry ice from his plane to the clouds below him.As was expected,snow formed and fell from the bottom of the cloud.Schaefer succeeded. He made history.Man did not succeed in making rain until quite__________.A:imaginativelyB:recentlyC:carefullyD:unscientificallyE:accidentallyF:satisfactorily

共用题干Rainmaking1 The idea of rainmaking is almost as old as man,but it was not until 1946 that man succeeded in making rain.In ancient times,rainmakers had claimed to bring rain by many methods:dancing.singing-Kiiiing animals t including humans).2 For a long time,men have understood where rain comes from.Water from the surface of oceans and lakes becomes part of the air,where it forms clouds from which rain falls.But exactly what starts the formation of raindrops was not known until quite recently.A man named John Aitken proved that drops of water gather around tiny bits of dust or other matter.The centers of the drops are so small that the human eye cannot see them.Without such centers,it seems raindrops do not form.3 During World War Ⅱ,Dr.Irving Langmir,and his assistant Schaefer,were hired by the General Electric Company to study how and why ice forms on the wings of airplanes.They went to a mountain in New Hampshire,where snowstorms are common and cold winds blow.They were surprised to find that often the temperature of the clouds surrounding them was far below the freezing point,and yet ice did not form in the clouds.4 After the War,Schaefer experimented with a machine that created cold,moist air similar to the air found in clouds.To imitate the moist air of a cloud,Schaefer would breathe into the machine.Then he would drop into the freezer a bit of powder,sugar,or some other substance.For weeks and months he tried everything he could imagine.Nothing happened.No crystals of ice were formed.None of the substances would serve as the center of a snow crystal or raindrops.5 One July morning,Schaefer was dropping in bits of various substances and watching the unsuccessful results.Finally,a friend suggested that they go to eat lunch and Schaefer went with him.As usual,he left the cover of the freezer up,since cold air sinks and would not escape from the box.6 Returning from lunch,Schaefer found that the temperature of the freezer had risen to a point higher than that required for ice crystals to remain solid.There were two choices now.He could close the cover and wait for the freezer itself to lower the air temperature,or he could make the process occur faster by adding dry ice-a gas in solid form that is very,very cold.He chose the latter plan.As he dropped the steaming white dry ice into the freezer,he happened to breathe out a large amount of air.And there,before his eyes,it happened!He had made ice crystals,not by adding centers to the moisture,but by cooling the breath so much that the liquid had to form crystals!Then he began to blow his breath into the freezer and drop large pieces of dry ice through it to create crystals which became a tiny snowstorm falling slowly to the floor of his laboratory.7 After planning carefully,Schaefer made an experiment by dropping dry ice from his plane to the clouds below him.As was expected,snow formed and fell from the bottom of the cloud.Schaefer succeeded.He made history.Paragraph 3______A:Langmir and Schaefer's Work for the GE CompanyB:Langmir and Schaefer's Discovery of Rain-formingC:Men's Knowledge of Rain-formingD:Schaefer's Several Unsuccessful ExperimentsE:Schaefer's Discovery by AccidentF:Langmir and Schaefer's Successful Cooneration

共用题干Rainmaking1 The idea of rainmaking is almost as old as man,but it was not until 1946 that man succeeded in making rain.In ancient times,rainmakers had claimed to bring rain by many methods:dancing,singing,killing animals(including humans).2 For a long time,men have understood where rain comes from.Water from the surface of oceans and lakes becomes part of the air,where it forms clouds from which rain falls.But exactly what starts the forma- tion of raindrops was not known until quite recently.A man named John Aitken proved that drops of water gather around tiny bits of dust or other matter. The centers of the drops are so small that the human eye can- not see them.Without such centers,it seems raindrops do not form.3 During World War Ⅱ,Dr. Irving Langmir,and his assistant Schaefer,were hired by the General Electric Company to study how and why ice forms on the wings of airplanes.They went to a mountain in New Hampshire,where snowstorms are common and cold winds blow. They were surprised to find that often the temperature of the clouds surrounding them was far below the freezing point,and yet ice did not form in the clouds.4 After the War,Schaefer experimented with a machine that created cold,moist air similar to the air found in clouds.To imitate the moist air of a cloud.Schaefer would breathe into the machine.Then he would drop into the freezer a bit of powder,sugar,or some other substance.For weeks and months he tried everything he could imagine.Nothing happened.No crystals of ice were formed.None of the substances would serve as the center of a snow crystal or raindrops.5 One July morning,Schaefer was dropping in bits of various substances and watching the unsuccessful results.Finally,a friend suggested that they go to eat lunch and Schaefer went with him.As usual,he left the cover of the freezer up,since cold air sinks and would not escape from the box.6 Returning from lunch,Schaefer found that the temperature of the freezer had risen to a point higher than that required for ice crystals to remain solid.There were two choices now.He could close the cover and wait for the freezer itself to lower the air temperature,or he could make the process occur faster by adding dry ice a gas in solid form that is very,very cold.He chose the latter plan.As he dropped the steaming white dry ice into the freezer,he happened to breathe out a large amount of air. And there,before his eyes,it happened ! He had made ice crystals,not by adding centers to the moisture,but by cooling the breath so much that the liquid had to form crystals!Then he began to blow his breath into the freezer and drop large pieces of dry ice through it to create crystals which became a tiny snowstorm falling slowly to the floor of his laboratory.7 After planning carefully,Schaefer made an experiment by dropping dry ice from his plane to the clouds below him.As was expected,snow formed and fell from the bottom of the cloud.Schaefer succeeded. He made history.Paragraph 6__________A:Langmir and Schaefer's Work for the GE CompanyB:Langmir and Schaefer's Discovery of Rain-formingC:Men'S Knowledge of Rain-formingD:Schaefer'S Several Unsuccessful Experiments E:Schaefer's Discovery by AccidentF: Langmir and Schaefer'S Successful Cooperation

共用题干Rainmaking1 The idea of rainmaking is almost as old as man,but it was not until 1946 that man succeeded in making rain.In ancient times,rainmakers had claimed to bring rain by many methods:dancing.singing-Kiiiing animals t including humans).2 For a long time,men have understood where rain comes from.Water from the surface of oceans and lakes becomes part of the air,where it forms clouds from which rain falls.But exactly what starts the formation of raindrops was not known until quite recently.A man named John Aitken proved that drops of water gather around tiny bits of dust or other matter.The centers of the drops are so small that the human eye cannot see them.Without such centers,it seems raindrops do not form.3 During World War Ⅱ,Dr.Irving Langmir,and his assistant Schaefer,were hired by the General Electric Company to study how and why ice forms on the wings of airplanes.They went to a mountain in New Hampshire,where snowstorms are common and cold winds blow.They were surprised to find that often the temperature of the clouds surrounding them was far below the freezing point,and yet ice did not form in the clouds.4 After the War,Schaefer experimented with a machine that created cold,moist air similar to the air found in clouds.To imitate the moist air of a cloud,Schaefer would breathe into the machine.Then he would drop into the freezer a bit of powder,sugar,or some other substance.For weeks and months he tried everything he could imagine.Nothing happened.No crystals of ice were formed.None of the substances would serve as the center of a snow crystal or raindrops.5 One July morning,Schaefer was dropping in bits of various substances and watching the unsuccessful results.Finally,a friend suggested that they go to eat lunch and Schaefer went with him.As usual,he left the cover of the freezer up,since cold air sinks and would not escape from the box.6 Returning from lunch,Schaefer found that the temperature of the freezer had risen to a point higher than that required for ice crystals to remain solid.There were two choices now.He could close the cover and wait for the freezer itself to lower the air temperature,or he could make the process occur faster by adding dry ice-a gas in solid form that is very,very cold.He chose the latter plan.As he dropped the steaming white dry ice into the freezer,he happened to breathe out a large amount of air.And there,before his eyes,it happened!He had made ice crystals,not by adding centers to the moisture,but by cooling the breath so much that the liquid had to form crystals!Then he began to blow his breath into the freezer and drop large pieces of dry ice through it to create crystals which became a tiny snowstorm falling slowly to the floor of his laboratory.7 After planning carefully,Schaefer made an experiment by dropping dry ice from his plane to the clouds below him.As was expected,snow formed and fell from the bottom of the cloud.Schaefer succeeded.He made history.Schaefer successfully made a field experiment on rainmaking after planning______.A:imaginativelyB:recentlyC:carefullyD:unscientifically E:accidentally F:satisfactorily

共用题干Rainmaking1 The idea of rainmaking is almost as old as man,but it was not until 1946 that man succeeded in making rain.In ancient times,rainmakers had claimed to bring rain by many methods:dancing.singing-Kiiiing animals t including humans).2 For a long time,men have understood where rain comes from.Water from the surface of oceans and lakes becomes part of the air,where it forms clouds from which rain falls.But exactly what starts the formation of raindrops was not known until quite recently.A man named John Aitken proved that drops of water gather around tiny bits of dust or other matter.The centers of the drops are so small that the human eye cannot see them.Without such centers,it seems raindrops do not form.3 During World War Ⅱ,Dr.Irving Langmir,and his assistant Schaefer,were hired by the General Electric Company to study how and why ice forms on the wings of airplanes.They went to a mountain in New Hampshire,where snowstorms are common and cold winds blow.They were surprised to find that often the temperature of the clouds surrounding them was far below the freezing point,and yet ice did not form in the clouds.4 After the War,Schaefer experimented with a machine that created cold,moist air similar to the air found in clouds.To imitate the moist air of a cloud,Schaefer would breathe into the machine.Then he would drop into the freezer a bit of powder,sugar,or some other substance.For weeks and months he tried everything he could imagine.Nothing happened.No crystals of ice were formed.None of the substances would serve as the center of a snow crystal or raindrops.5 One July morning,Schaefer was dropping in bits of various substances and watching the unsuccessful results.Finally,a friend suggested that they go to eat lunch and Schaefer went with him.As usual,he left the cover of the freezer up,since cold air sinks and would not escape from the box.6 Returning from lunch,Schaefer found that the temperature of the freezer had risen to a point higher than that required for ice crystals to remain solid.There were two choices now.He could close the cover and wait for the freezer itself to lower the air temperature,or he could make the process occur faster by adding dry ice-a gas in solid form that is very,very cold.He chose the latter plan.As he dropped the steaming white dry ice into the freezer,he happened to breathe out a large amount of air.And there,before his eyes,it happened!He had made ice crystals,not by adding centers to the moisture,but by cooling the breath so much that the liquid had to form crystals!Then he began to blow his breath into the freezer and drop large pieces of dry ice through it to create crystals which became a tiny snowstorm falling slowly to the floor of his laboratory.7 After planning carefully,Schaefer made an experiment by dropping dry ice from his plane to the clouds below him.As was expected,snow formed and fell from the bottom of the cloud.Schaefer succeeded.He made history.In ancient times,rainmakers tried to make rain for dry lands,but______.A:imaginativelyB:recentlyC:carefullyD:unscientifically E:accidentally F:satisfactorily

共用题干Rainmaking1 The idea of rainmaking is almost as old as man,but it was not until 1946 that man succeeded in making rain.In ancient times,rainmakers had claimed to bring rain by many methods:dancing.singing-Kiiiing animals t including humans).2 For a long time,men have understood where rain comes from.Water from the surface of oceans and lakes becomes part of the air,where it forms clouds from which rain falls.But exactly what starts the formation of raindrops was not known until quite recently.A man named John Aitken proved that drops of water gather around tiny bits of dust or other matter.The centers of the drops are so small that the human eye cannot see them.Without such centers,it seems raindrops do not form.3 During World War Ⅱ,Dr.Irving Langmir,and his assistant Schaefer,were hired by the General Electric Company to study how and why ice forms on the wings of airplanes.They went to a mountain in New Hampshire,where snowstorms are common and cold winds blow.They were surprised to find that often the temperature of the clouds surrounding them was far below the freezing point,and yet ice did not form in the clouds.4 After the War,Schaefer experimented with a machine that created cold,moist air similar to the air found in clouds.To imitate the moist air of a cloud,Schaefer would breathe into the machine.Then he would drop into the freezer a bit of powder,sugar,or some other substance.For weeks and months he tried everything he could imagine.Nothing happened.No crystals of ice were formed.None of the substances would serve as the center of a snow crystal or raindrops.5 One July morning,Schaefer was dropping in bits of various substances and watching the unsuccessful results.Finally,a friend suggested that they go to eat lunch and Schaefer went with him.As usual,he left the cover of the freezer up,since cold air sinks and would not escape from the box.6 Returning from lunch,Schaefer found that the temperature of the freezer had risen to a point higher than that required for ice crystals to remain solid.There were two choices now.He could close the cover and wait for the freezer itself to lower the air temperature,or he could make the process occur faster by adding dry ice-a gas in solid form that is very,very cold.He chose the latter plan.As he dropped the steaming white dry ice into the freezer,he happened to breathe out a large amount of air.And there,before his eyes,it happened!He had made ice crystals,not by adding centers to the moisture,but by cooling the breath so much that the liquid had to form crystals!Then he began to blow his breath into the freezer and drop large pieces of dry ice through it to create crystals which became a tiny snowstorm falling slowly to the floor of his laboratory.7 After planning carefully,Schaefer made an experiment by dropping dry ice from his plane to the clouds below him.As was expected,snow formed and fell from the bottom of the cloud.Schaefer succeeded.He made history.Schaefer found a way of how to make ice crystals______.A:imaginativelyB:recentlyC:carefullyD:unscientifically E:accidentally F:satisfactorily

共用题干Rainmaking1 The idea of rainmaking is almost as old as man,but it was not until 1946 that man succeeded in making rain.In ancient times,rainmakers had claimed to bring rain by many methods:dancing,singing,killing animals(including humans).2 For a long time,men have understood where rain comes from.Water from the surface of oceans and lakes becomes part of the air,where it forms clouds from which rain falls.But exactly what starts the forma- tion of raindrops was not known until quite recently.A man named John Aitken proved that drops of water gather around tiny bits of dust or other matter. The centers of the drops are so small that the human eye can- not see them.Without such centers,it seems raindrops do not form.3 During World War Ⅱ,Dr. Irving Langmir,and his assistant Schaefer,were hired by the General Electric Company to study how and why ice forms on the wings of airplanes.They went to a mountain in New Hampshire,where snowstorms are common and cold winds blow. They were surprised to find that often the temperature of the clouds surrounding them was far below the freezing point,and yet ice did not form in the clouds.4 After the War,Schaefer experimented with a machine that created cold,moist air similar to the air found in clouds.To imitate the moist air of a cloud.Schaefer would breathe into the machine.Then he would drop into the freezer a bit of powder,sugar,or some other substance.For weeks and months he tried everything he could imagine.Nothing happened.No crystals of ice were formed.None of the substances would serve as the center of a snow crystal or raindrops.5 One July morning,Schaefer was dropping in bits of various substances and watching the unsuccessful results.Finally,a friend suggested that they go to eat lunch and Schaefer went with him.As usual,he left the cover of the freezer up,since cold air sinks and would not escape from the box.6 Returning from lunch,Schaefer found that the temperature of the freezer had risen to a point higher than that required for ice crystals to remain solid.There were two choices now.He could close the cover and wait for the freezer itself to lower the air temperature,or he could make the process occur faster by adding dry ice a gas in solid form that is very,very cold.He chose the latter plan.As he dropped the steaming white dry ice into the freezer,he happened to breathe out a large amount of air. And there,before his eyes,it happened ! He had made ice crystals,not by adding centers to the moisture,but by cooling the breath so much that the liquid had to form crystals!Then he began to blow his breath into the freezer and drop large pieces of dry ice through it to create crystals which became a tiny snowstorm falling slowly to the floor of his laboratory.7 After planning carefully,Schaefer made an experiment by dropping dry ice from his plane to the clouds below him.As was expected,snow formed and fell from the bottom of the cloud.Schaefer succeeded. He made history.In ancient times,rainmakers tried to make rain for dry lands,but________.A:imaginativelyB:recentlyC:carefullyD:unscientificallyE:accidentallyF:satisfactorily

共用题干Rainmaking1 The idea of rainmaking is almost as old as man,but it was not until 1946 that man succeeded in making rain.In ancient times,rainmakers had claimed to bring rain by many methods:dancing,singing,killing animals(including humans).2 For a long time,men have understood where rain comes from.Water from the surface of oceans and lakes becomes part of the air,where it forms clouds from which rain falls.But exactly what starts the forma- tion of raindrops was not known until quite recently.A man named John Aitken proved that drops of water gather around tiny bits of dust or other matter. The centers of the drops are so small that the human eye can- not see them.Without such centers,it seems raindrops do not form.3 During World War Ⅱ,Dr. Irving Langmir,and his assistant Schaefer,were hired by the General Electric Company to study how and why ice forms on the wings of airplanes.They went to a mountain in New Hampshire,where snowstorms are common and cold winds blow. They were surprised to find that often the temperature of the clouds surrounding them was far below the freezing point,and yet ice did not form in the clouds.4 After the War,Schaefer experimented with a machine that created cold,moist air similar to the air found in clouds.To imitate the moist air of a cloud.Schaefer would breathe into the machine.Then he would drop into the freezer a bit of powder,sugar,or some other substance.For weeks and months he tried everything he could imagine.Nothing happened.No crystals of ice were formed.None of the substances would serve as the center of a snow crystal or raindrops.5 One July morning,Schaefer was dropping in bits of various substances and watching the unsuccessful results.Finally,a friend suggested that they go to eat lunch and Schaefer went with him.As usual,he left the cover of the freezer up,since cold air sinks and would not escape from the box.6 Returning from lunch,Schaefer found that the temperature of the freezer had risen to a point higher than that required for ice crystals to remain solid.There were two choices now.He could close the cover and wait for the freezer itself to lower the air temperature,or he could make the process occur faster by adding dry ice a gas in solid form that is very,very cold.He chose the latter plan.As he dropped the steaming white dry ice into the freezer,he happened to breathe out a large amount of air. And there,before his eyes,it happened ! He had made ice crystals,not by adding centers to the moisture,but by cooling the breath so much that the liquid had to form crystals!Then he began to blow his breath into the freezer and drop large pieces of dry ice through it to create crystals which became a tiny snowstorm falling slowly to the floor of his laboratory.7 After planning carefully,Schaefer made an experiment by dropping dry ice from his plane to the clouds below him.As was expected,snow formed and fell from the bottom of the cloud.Schaefer succeeded. He made history.Paragraph 2_________ A:Langmir and Schaefer's Work for the GE CompanyB:Langmir and Schaefer's Discovery of Rain-formingC:Men'S Knowledge of Rain-formingD:Schaefer'S Several Unsuccessful Experiments E:Schaefer's Discovery by AccidentF: Langmir and Schaefer'S Successful Cooperation

共用题干Rainmaking1 The idea of rainmaking is almost as old as man,but it was not until 1946 that man succeeded in making rain.In ancient times,rainmakers had claimed to bring rain by many methods:dancing,singing,killing animals(including humans).2 For a long time,men have understood where rain comes from.Water from the surface of oceans and lakes becomes part of the air,where it forms clouds from which rain falls.But exactly what starts the forma- tion of raindrops was not known until quite recently.A man named John Aitken proved that drops of water gather around tiny bits of dust or other matter. The centers of the drops are so small that the human eye can- not see them.Without such centers,it seems raindrops do not form.3 During World War Ⅱ,Dr. Irving Langmir,and his assistant Schaefer,were hired by the General Electric Company to study how and why ice forms on the wings of airplanes.They went to a mountain in New Hampshire,where snowstorms are common and cold winds blow. They were surprised to find that often the temperature of the clouds surrounding them was far below the freezing point,and yet ice did not form in the clouds.4 After the War,Schaefer experimented with a machine that created cold,moist air similar to the air found in clouds.To imitate the moist air of a cloud.Schaefer would breathe into the machine.Then he would drop into the freezer a bit of powder,sugar,or some other substance.For weeks and months he tried everything he could imagine.Nothing happened.No crystals of ice were formed.None of the substances would serve as the center of a snow crystal or raindrops.5 One July morning,Schaefer was dropping in bits of various substances and watching the unsuccessful results.Finally,a friend suggested that they go to eat lunch and Schaefer went with him.As usual,he left the cover of the freezer up,since cold air sinks and would not escape from the box.6 Returning from lunch,Schaefer found that the temperature of the freezer had risen to a point higher than that required for ice crystals to remain solid.There were two choices now.He could close the cover and wait for the freezer itself to lower the air temperature,or he could make the process occur faster by adding dry ice a gas in solid form that is very,very cold.He chose the latter plan.As he dropped the steaming white dry ice into the freezer,he happened to breathe out a large amount of air. And there,before his eyes,it happened ! He had made ice crystals,not by adding centers to the moisture,but by cooling the breath so much that the liquid had to form crystals!Then he began to blow his breath into the freezer and drop large pieces of dry ice through it to create crystals which became a tiny snowstorm falling slowly to the floor of his laboratory.7 After planning carefully,Schaefer made an experiment by dropping dry ice from his plane to the clouds below him.As was expected,snow formed and fell from the bottom of the cloud.Schaefer succeeded. He made history.Schaefer successfully made a field experiment on rainmaking after planning_________. A:imaginativelyB:recentlyC:carefullyD:unscientificallyE:accidentallyF:satisfactorily

共用题干Rainmaking1 The idea of rainmaking is almost as old as man,but it was not until 1946 that man succeeded in making rain.In ancient times,rainmakers had claimed to bring rain by many methods:dancing.singing-Kiiiing animals t including humans).2 For a long time,men have understood where rain comes from.Water from the surface of oceans and lakes becomes part of the air,where it forms clouds from which rain falls.But exactly what starts the formation of raindrops was not known until quite recently.A man named John Aitken proved that drops of water gather around tiny bits of dust or other matter.The centers of the drops are so small that the human eye cannot see them.Without such centers,it seems raindrops do not form.3 During World War Ⅱ,Dr.Irving Langmir,and his assistant Schaefer,were hired by the General Electric Company to study how and why ice forms on the wings of airplanes.They went to a mountain in New Hampshire,where snowstorms are common and cold winds blow.They were surprised to find that often the temperature of the clouds surrounding them was far below the freezing point,and yet ice did not form in the clouds.4 After the War,Schaefer experimented with a machine that created cold,moist air similar to the air found in clouds.To imitate the moist air of a cloud,Schaefer would breathe into the machine.Then he would drop into the freezer a bit of powder,sugar,or some other substance.For weeks and months he tried everything he could imagine.Nothing happened.No crystals of ice were formed.None of the substances would serve as the center of a snow crystal or raindrops.5 One July morning,Schaefer was dropping in bits of various substances and watching the unsuccessful results.Finally,a friend suggested that they go to eat lunch and Schaefer went with him.As usual,he left the cover of the freezer up,since cold air sinks and would not escape from the box.6 Returning from lunch,Schaefer found that the temperature of the freezer had risen to a point higher than that required for ice crystals to remain solid.There were two choices now.He could close the cover and wait for the freezer itself to lower the air temperature,or he could make the process occur faster by adding dry ice-a gas in solid form that is very,very cold.He chose the latter plan.As he dropped the steaming white dry ice into the freezer,he happened to breathe out a large amount of air.And there,before his eyes,it happened!He had made ice crystals,not by adding centers to the moisture,but by cooling the breath so much that the liquid had to form crystals!Then he began to blow his breath into the freezer and drop large pieces of dry ice through it to create crystals which became a tiny snowstorm falling slowly to the floor of his laboratory.7 After planning carefully,Schaefer made an experiment by dropping dry ice from his plane to the clouds below him.As was expected,snow formed and fell from the bottom of the cloud.Schaefer succeeded.He made history.Man did not succeed in making rain until quite______.A:imaginativelyB:recentlyC:carefullyD:unscientifically E:accidentally F:satisfactorily

共用题干Old Man Myths and Realities1.When does a middle-aged man become an old man?Officially,of course,it is when we reach retirement age. But, as we all know, this is a fairly blunt(生硬的)method of decision making. As life expectancy(寿命)increases,retirement planning needs to be changed. This is because being an old man today is very different from what it was a generation or so ago.2.Sixty-five is the new middle-aged man. These days people are talking about the young-old, that is ages 70-75,and those over 75 as the old-old. The young-old frequently continue in good health and maintain strong links with friends and family.The old-old have a much higher chance of poor health and social isolation.3.Although men are living longer,there are still more old women than old men.This fact alone should arouse interest as to why. Relatively little is actually known about why this is the case or about the experiences of the old man.Sure,we are aware that the old man experiences anxiety,financial problems,loneliness,etc.,but that is really about all we know.4.It is usually believed that the old man often complains about their health.In fact,most old man think their health is good even though most are diagnosed with at least one chronic illness.The physical health of the old man is strongly affected by their health behavior when they were younger.Paragraph 4______A:New Definitions of the Old ManB:Changing Concept of the Old ManC:Health of the Old ManD:Happy Old Man and Sad Old ManE:Limited Knowledge of the Old Man's Experiences F: Contempt for the Old Man

共用题干Old Man Myths and Realities1.When does a middle-aged man become an old man?Officially,of course,it is when we reach retirement age. But, as we all know, this is a fairly blunt(生硬的)method of decision making. As life expectancy(寿命)increases,retirement planning needs to be changed. This is because being an old man today is very different from what it was a generation or so ago.2.Sixty-five is the new middle-aged man. These days people are talking about the young-old, that is ages 70-75,and those over 75 as the old-old. The young-old frequently continue in good health and maintain strong links with friends and family.The old-old have a much higher chance of poor health and social isolation.3.Although men are living longer,there are still more old women than old men.This fact alone should arouse interest as to why. Relatively little is actually known about why this is the case or about the experiences of the old man.Sure,we are aware that the old man experiences anxiety,financial problems,loneliness,etc.,but that is really about all we know.4.It is usually believed that the old man often complains about their health.In fact,most old man think their health is good even though most are diagnosed with at least one chronic illness.The physical health of the old man is strongly affected by their health behavior when they were younger.A man in his mid-60s is now regarded as______.A:in good healthB:in the pastC:in the wrongD:the old manE:a middle-aged man F: a young man

共用题干Old Man Myths and Realities1.When does a middle-aged man become an old man?Officially,of course,it is when we reach retirement age. But, as we all know, this is a fairly blunt(生硬的)method of decision making. As life expectancy(寿命)increases,retirement planning needs to be changed. This is because being an old man today is very different from what it was a generation or so ago.2.Sixty-five is the new middle-aged man. These days people are talking about the young-old, that is ages 70-75,and those over 75 as the old-old. The young-old frequently continue in good health and maintain strong links with friends and family.The old-old have a much higher chance of poor health and social isolation.3.Although men are living longer,there are still more old women than old men.This fact alone should arouse interest as to why. Relatively little is actually known about why this is the case or about the experiences of the old man.Sure,we are aware that the old man experiences anxiety,financial problems,loneliness,etc.,but that is really about all we know.4.It is usually believed that the old man often complains about their health.In fact,most old man think their health is good even though most are diagnosed with at least one chronic illness.The physical health of the old man is strongly affected by their health behavior when they were younger.Paragraph 2______A:New Definitions of the Old ManB:Changing Concept of the Old ManC:Health of the Old ManD:Happy Old Man and Sad Old ManE:Limited Knowledge of the Old Man's Experiences F: Contempt for the Old Man

共用题干Old Man Myths and Realities1.When does a middle-aged man become an old man?Officially,of course,it is when we reach retirement age. But, as we all know, this is a fairly blunt(生硬的)method of decision making. As life expectancy(寿命)increases,retirement planning needs to be changed. This is because being an old man today is very different from what it was a generation or so ago.2.Sixty-five is the new middle-aged man. These days people are talking about the young-old, that is ages 70-75,and those over 75 as the old-old. The young-old frequently continue in good health and maintain strong links with friends and family.The old-old have a much higher chance of poor health and social isolation.3.Although men are living longer,there are still more old women than old men.This fact alone should arouse interest as to why. Relatively little is actually known about why this is the case or about the experiences of the old man.Sure,we are aware that the old man experiences anxiety,financial problems,loneliness,etc.,but that is really about all we know.4.It is usually believed that the old man often complains about their health.In fact,most old man think their health is good even though most are diagnosed with at least one chronic illness.The physical health of the old man is strongly affected by their health behavior when they were younger.Nowadays men generally live longer than______.A:in good healthB:in the pastC:in the wrongD:the old manE:a middle-aged man F: a young man

共用题干Old Man Myths and Realities1.When does a middle-aged man become an old man?Officially,of course,it is when we reach retirement age. But, as we all know, this is a fairly blunt(生硬的)method of decision making. As life expectancy(寿命)increases,retirement planning needs to be changed. This is because being an old man today is very different from what it was a generation or so ago.2.Sixty-five is the new middle-aged man. These days people are talking about the young-old, that is ages 70-75,and those over 75 as the old-old. The young-old frequently continue in good health and maintain strong links with friends and family.The old-old have a much higher chance of poor health and social isolation.3.Although men are living longer,there are still more old women than old men.This fact alone should arouse interest as to why. Relatively little is actually known about why this is the case or about the experiences of the old man.Sure,we are aware that the old man experiences anxiety,financial problems,loneliness,etc.,but that is really about all we know.4.It is usually believed that the old man often complains about their health.In fact,most old man think their health is good even though most are diagnosed with at least one chronic illness.The physical health of the old man is strongly affected by their health behavior when they were younger.Most old men consider themselves to be______.A:in good healthB:in the pastC:in the wrongD:the old manE:a middle-aged man F: a young man

A police officer claimed that the young man had attempted to()paying his fare.AavoidBrejectCrefuseDneglect

单选题A police officer claimed that the young man had attempted to()paying his fare.AavoidBrejectCrefuseDneglect

单选题We met the old man _____ times on the way home.Adozen ofBdozenCdozensDdozens of