Many people believe the glare from snow causes snow-blindness． Yet, dark glasses or not,they find themselves suffering from headaches and watering eyes, and even snow-blindness, when exposed to several hours of "snow light"．The United States Army has now determined that glare from snow does not cause snow-blindness in troops in a snow-covered country． Rather, a man's eyes frequently find nothing to focus on in a broad expanse of barren snow-covered terrain． So his gaze continually shifts and jumps back and forth over the entire landscape in search of something to look at． Finding nothing,hour after hour, the eyes never stop searching and the eyeballs become sore and the eye musclesache． Nature offsets this irritation by producing more and fluid which covers the eyeball． The fluid covers the eyeball in increasing quantity until vision blurs, then is observed, and the result istotal, even though temporary, snow-blindness．Experiments led the Army to a simple method of overcoming this problem． Scouts ahead of a main body of troops are trained to shake snow from evergreen bushes, creating a dotted line as they cross completely snow-covered landscape． Even the scouts themselves throw lightweight, dark colored objects ahead on which they too can focus． The men following can then see something．Their gaze is arrested． Their eyes focus on a bush and having found something to see, stop scouring the snow-blanketed landscape． By focusing their attention on one object at a time, the men can cross the snow without becoming hopelessly snow-blind or lost． In this way the problem of crossing a solid white terrain is overcome．A suitable title for this passage would be __________ ．A.Snow-Blindness and How to Overcome ItB.Nature's Cure for Snow BlindnessC.Soldiers in the SnowD.Snow Vision
Many people believe the glare from snow causes snow-blindness． Yet, dark glasses or not,they find themselves suffering from headaches and watering eyes, and even snow-blindness, when exposed to several hours of "snow light"．
The United States Army has now determined that glare from snow does not cause snow-
blindness in troops in a snow-covered country． Rather, a man's eyes frequently find nothing to focus on in a broad expanse of barren snow-covered terrain． So his gaze continually shifts and jumps back and forth over the entire landscape in search of something to look at． Finding nothing,hour after hour, the eyes never stop searching and the eyeballs become sore and the eye musclesache． Nature offsets this irritation by producing more and fluid which covers the eyeball． The fluid covers the eyeball in increasing quantity until vision blurs, then is observed, and the result is
total, even though temporary, snow-blindness．
Experiments led the Army to a simple method of overcoming this problem． Scouts ahead of a main body of troops are trained to shake snow from evergreen bushes, creating a dotted line as they cross completely snow-covered landscape． Even the scouts themselves throw lightweight, dark colored objects ahead on which they too can focus． The men following can then see something．Their gaze is arrested． Their eyes focus on a bush and having found something to see, stop scouring the snow-blanketed landscape． By focusing their attention on one object at a time, the men can cross the snow without becoming hopelessly snow-blind or lost． In this way the problem of crossing a solid white terrain is overcome．
A suitable title for this passage would be __________ ．
The United States Army has now determined that glare from snow does not cause snow-
blindness in troops in a snow-covered country． Rather, a man's eyes frequently find nothing to focus on in a broad expanse of barren snow-covered terrain． So his gaze continually shifts and jumps back and forth over the entire landscape in search of something to look at． Finding nothing,hour after hour, the eyes never stop searching and the eyeballs become sore and the eye musclesache． Nature offsets this irritation by producing more and fluid which covers the eyeball． The fluid covers the eyeball in increasing quantity until vision blurs, then is observed, and the result is
total, even though temporary, snow-blindness．
Experiments led the Army to a simple method of overcoming this problem． Scouts ahead of a main body of troops are trained to shake snow from evergreen bushes, creating a dotted line as they cross completely snow-covered landscape． Even the scouts themselves throw lightweight, dark colored objects ahead on which they too can focus． The men following can then see something．Their gaze is arrested． Their eyes focus on a bush and having found something to see, stop scouring the snow-blanketed landscape． By focusing their attention on one object at a time, the men can cross the snow without becoming hopelessly snow-blind or lost． In this way the problem of crossing a solid white terrain is overcome．
A suitable title for this passage would be __________ ．
A.Snow-Blindness and How to Overcome It
B.Nature's Cure for Snow Blindness
C.Soldiers in the Snow
D.Snow Vision
B.Nature's Cure for Snow Blindness
C.Soldiers in the Snow
D.Snow Vision
参考解析
解析：本题考查全文主旨。全文讲的就是雪盲症怎么发生、怎么应对，故选A。
相关考题：
Passage TwoWhen we see well, we do not think about our eyes very often. It is only when we cannot see perfectly that we realize how important our eyes are.People who are nearsighted can only see things that are very close to their eyes. Everything else is not so clear. Many people who do a lot of close work, such as writing, reading and sewing, become near sighted. Then they have to wear glasses in order to see distant (远处的) things clearly'.People who are nearsighted suffer from just the opposite problem. They can see things that are far away, but they have difficulty in reading a book unless they hold it at arm's length. If they want to do much reading, they must get glasses, too.Other people do not see clearly because their eyes are not exactly the right shape. They have what is called astigmatism (散光). This, too, can be corrected by glasses. Some people's eyes become cloudy because of cataracts (白内障). Long ago these people often became blind. Now, however, it is possible to operate on the cataracts and remove them.Having two good eyes is important for judging distances. Each eye sees things from a slightly different angle (角度). To prove this to yourself, look at an object out of one eye; then look at the same object outof the other eye. You will find the object's relation to the background (背景) and other things around it has changed. The difference between these two different eye views helps us to judge how far away an object is. People who have only one eye cannot judge distance as people with two eyes.40. We should take good care of our eyes ______.A. only when we cannot see perfectlyB. only when we can see wellC. even if we can see wellD. only when we realize how important our eyes are
People who suffer from astigmatismA. have a curable disease in their eyesB. have eyes that are not exactly the right shapeC. have a difficulty that can be corrected by an operationD. have an eye difficulty that cannot be corrected by glasses
Many people believe the glare from snow causes snow blindness.Yet, with dark glasses or not, they find themselves suffering from headaches and watering eyes, and even snowblindness, when exposed to several hours of "snow light". The United States Army has now determined that the glare from snow does not cause snow-blindness in troops in a snow-covered country.Rather, a mans eyes frequently find nothing to focus on in a broad expanse of a snow-covered area.So his gaze continually shifts and jumps back and forth over the entire landscape in search of something to look at.Finding nothing, hour after hour, the eyes never stop searching and the eyeballs become sore and the eye muscle aches.Nature balances this annoyance by producing more and more liquid which covers the eyeballs.The liquid covers the eyeballs in increasing quantity until vision blurs.And the result is total,even though temporary,snowblindness. Experiments led the Army to a simple method of overcoming this problem.Scouts ahead of a main body of troops are trained to shake snow from evergreen bushes, creating a dotted line as they cross completely snow-covered landscape.Even the scouts themselves throw lightweight, dark-colored objects ahead on which they too can focus. The men following can then see something.Their gaze is arrested.Their eyes focus on a bush and having found something to see, stop searching through the snow- blanketed landscape.By focusing their attention on one object at a time, the man can cross the snow withoutbecoming hopelessly snowblind or lost.In this way the problem of crossing a solid white area is overcome.The eyeballs become sore and the eye muscles ache because______.A．tears cover the eyeballsB．the eyes are annoyed by blinding sunlightC．the eyes are annoyed by blinding snowD．there is nothing to focus on
People suffering from accidents incurred at work or from occupational diseases receive preferential treatment by the social security service compared with those suffering from civil accidents and ordinary illnesses.
The reason that many people find it hard to relax these days is that________．A．they are suffering from the effects of excessive stressB．they are working harder than they used toC．they are often too busy to find timeD．they have no idea what relaxation means to them
Many people believe the glare from snow causes snow-blindness． Yet, dark glasses or not,they find themselves suffering from headaches and watering eyes, and even snow-blindness, when exposed to several hours of "snow light"．The United States Army has now determined that glare from snow does not cause snow-blindness in troops in a snow-covered country． Rather, a man's eyes frequently find nothing to focus on in a broad expanse of barren snow-covered terrain． So his gaze continually shifts and jumps back and forth over the entire landscape in search of something to look at． Finding nothing,hour after hour, the eyes never stop searching and the eyeballs become sore and the eye musclesache． Nature offsets this irritation by producing more and fluid which covers the eyeball． The fluid covers the eyeball in increasing quantity until vision blurs, then is observed, and the result istotal, even though temporary, snow-blindness．Experiments led the Army to a simple method of overcoming this problem． Scouts ahead of a main body of troops are trained to shake snow from evergreen bushes, creating a dotted line as they cross completely snow-covered landscape． Even the scouts themselves throw lightweight, dark colored objects ahead on which they too can focus． The men following can then see something．Their gaze is arrested． Their eyes focus on a bush and having found something to see, stop scouring the snow-blanketed landscape． By focusing their attention on one object at a time, the men can cross the snow without becoming hopelessly snow-blind or lost． In this way the problem of crossing a solid white terrain is overcome．?The scouts shake snow from evergreen bushes in order to__________ ．A.give the men behind something to seeB.beautify the landscapeC.warm themselves in the coldD.prevent the men behind from losing their way
Many people believe the glare from snow causes snow-blindness． Yet, dark glasses or not,they find themselves suffering from headaches and watering eyes, and even snow-blindness, when exposed to several hours of "snow light"．The United States Army has now determined that glare from snow does not cause snow-blindness in troops in a snow-covered country． Rather, a man's eyes frequently find nothing to focus on in a broad expanse of barren snow-covered terrain． So his gaze continually shifts and jumps back and forth over the entire landscape in search of something to look at． Finding nothing,hour after hour, the eyes never stop searching and the eyeballs become sore and the eye musclesache． Nature offsets this irritation by producing more and fluid which covers the eyeball． The fluid covers the eyeball in increasing quantity until vision blurs, then is observed, and the result istotal, even though temporary, snow-blindness．Experiments led the Army to a simple method of overcoming this problem． Scouts ahead of a main body of troops are trained to shake snow from evergreen bushes, creating a dotted line as they cross completely snow-covered landscape． Even the scouts themselves throw lightweight, dark colored objects ahead on which they too can focus． The men following can then see something．Their gaze is arrested． Their eyes focus on a bush and having found something to see, stop scouring the snow-blanketed landscape． By focusing their attention on one object at a time, the men can cross the snow without becoming hopelessly snow-blind or lost． In this way the problem of crossing a solid white terrain is overcome．Snow-blindness may be avoided by__________ A.concentrating to the solid white terrainB.searching for something to look at in snow-covered terrainC.providing the eyes with something to focus onD.covering the eyeballs with fluid
Many people believe the glare from snow causes snow-blindness． Yet, dark glasses or not,they find themselves suffering from headaches and watering eyes, and even snow-blindness, when exposed to several hours of "snow light"．The United States Army has now determined that glare from snow does not cause snow-blindness in troops in a snow-covered country． Rather, a man's eyes frequently find nothing to focus on in a broad expanse of barren snow-covered terrain． So his gaze continually shifts and jumps back and forth over the entire landscape in search of something to look at． Finding nothing,hour after hour, the eyes never stop searching and the eyeballs become sore and the eye musclesache． Nature offsets this irritation by producing more and fluid which covers the eyeball． The fluid covers the eyeball in increasing quantity until vision blurs, then is observed, and the result istotal, even though temporary, snow-blindness．Experiments led the Army to a simple method of overcoming this problem． Scouts ahead of a main body of troops are trained to shake snow from evergreen bushes, creating a dotted line as they cross completely snow-covered landscape． Even the scouts themselves throw lightweight, dark colored objects ahead on which they too can focus． The men following can then see something．Their gaze is arrested． Their eyes focus on a bush and having found something to see, stop scouring the snow-blanketed landscape． By focusing their attention on one object at a time, the men can cross the snow without becoming hopelessly snow-blind or lost． In this way the problem of crossing a solid white terrain is overcome．To prevent headaches, watering eyes and blindness caused by the glare from snow, dark glasses are__________ ．A.indispensibleB.usefulC.ineffectiveD.available
Many people believe the glare from snow causes snow-blindness． Yet, dark glasses or not,they find themselves suffering from headaches and watering eyes, and even snow-blindness, when exposed to several hours of "snow light"．The United States Army has now determined that glare from snow does not cause snow-blindness in troops in a snow-covered country． Rather, a man's eyes frequently find nothing to focus on in a broad expanse of barren snow-covered terrain． So his gaze continually shifts and jumps back and forth over the entire landscape in search of something to look at． Finding nothing,hour after hour, the eyes never stop searching and the eyeballs become sore and the eye musclesache． Nature offsets this irritation by producing more and fluid which covers the eyeball． The fluid covers the eyeball in increasing quantity until vision blurs, then is observed, and the result istotal, even though temporary, snow-blindness．Experiments led the Army to a simple method of overcoming this problem． Scouts ahead of a main body of troops are trained to shake snow from evergreen bushes, creating a dotted line as they cross completely snow-covered landscape． Even the scouts themselves throw lightweight, dark colored objects ahead on which they too can focus． The men following can then see something．Their gaze is arrested． Their eyes focus on a bush and having found something to see, stop scouring the snow-blanketed landscape． By focusing their attention on one object at a time, the men can cross the snow without becoming hopelessly snow-blind or lost． In this way the problem of crossing a solid white terrain is overcome．?When the eyes are sore tears are produced toA.clear the visionB.remedy snow-blindnessC.ease the irritationD.loosen the muscles
Many people believe the glare from snow causes snow-blindness. Yet, dark glasses or not, they find themselves suffering from headaches and watering eyes, and even snow-blindness, when exposed to several hours of "snow light". The United States Army has now determined that glare from snow does not cause snow- blindness in troops in a snow-covered country. Rather, a man's eyes frequently find nothing to focus on in a broad expanse of barren snow-covered terrain. So his gaze continually shifts and jumps back and forth over the entire landscape in search of something to look at. Finding nothing, hour after hour, the eyes never stop searching and the eyeballs become sore and the eye muscles ache. Nature offsets this irritation by producing more and fluid which covers the eyeball. The fluid covers the eyeball in increasing quantity until vision blurs,then is observed, and the result is total, even though temporary, snow-blindness. Experiments led the Army to a simple method of overcoming this problem. Scouts ahead of a main body of troops are trained to shake snow from evergreen bushes, creating a dotted line as they cross completely snow-covered landscape. Even the scouts themselves throw lightweight, dark colored objects ahead on which they too can focus. The men following can then see something. Their gaze is arrested. Their eyes focus on a bush and having found something to see, stop scouring the snow-blanketed landscape. By focusing their attention on one object at a time, the men can cross the snow without becoming hopelessly snow-blind or lost. In this way the problem of crossing a solid white terrain is overcome. A suitable title for this passage would be_________.A. snow-blindness and how to overcome itB. nature's cure for snow blindnessC. soldiers in the snowD. snow vision
Many people believe the glare from snow causes snow-blindness. Yet, dark glasses or not, they find themselves suffering from headaches and watering eyes, and even snow-blindness, when exposed to several hours of "snow light". The United States Army has now determined that glare from snow does not cause snow- blindness in troops in a snow-covered country. Rather, a man's eyes frequently find nothing to focus on in a broad expanse of barren snow-covered terrain. So his gaze continually shifts and jumps back and forth over the entire landscape in search of something to look at. Finding nothing, hour after hour, the eyes never stop searching and the eyeballs become sore and the eye muscles ache. Nature offsets this irritation by producing more and fluid which covers the eyeball. The fluid covers the eyeball in increasing quantity until vision blurs,then is observed, and the result is total, even though temporary, snow-blindness. Experiments led the Army to a simple method of overcoming this problem. Scouts ahead of a main body of troops are trained to shake snow from evergreen bushes, creating a dotted line as they cross completely snow-covered landscape. Even the scouts themselves throw lightweight, dark colored objects ahead on which they too can focus. The men following can then see something. Their gaze is arrested. Their eyes focus on a bush and having found something to see, stop scouring the snow-blanketed landscape. By focusing their attention on one object at a time, the men can cross the snow without becoming hopelessly snow-blind or lost. In this way the problem of crossing a solid white terrain is overcome.Snow-blindness may be avoided by_________.A. concentrating to the solid white terrainB. searching for something to look at in snow-covered terrainC. providing the eyes with something to focus onD. covering the eyeballs with fluid
Many people believe the glare from snow causes snow-blindness. Yet, dark glasses or not, they find themselves suffering from headaches and watering eyes, and even snow-blindness, when exposed to several hours of "snow light". The United States Army has now determined that glare from snow does not cause snow- blindness in troops in a snow-covered country. Rather, a man's eyes frequently find nothing to focus on in a broad expanse of barren snow-covered terrain. So his gaze continually shifts and jumps back and forth over the entire landscape in search of something to look at. Finding nothing, hour after hour, the eyes never stop searching and the eyeballs become sore and the eye muscles ache. Nature offsets this irritation by producing more and fluid which covers the eyeball. The fluid covers the eyeball in increasing quantity until vision blurs,then is observed, and the result is total, even though temporary, snow-blindness. Experiments led the Army to a simple method of overcoming this problem. Scouts ahead of a main body of troops are trained to shake snow from evergreen bushes, creating a dotted line as they cross completely snow-covered landscape. Even the scouts themselves throw lightweight, dark colored objects ahead on which they too can focus. The men following can then see something. Their gaze is arrested. Their eyes focus on a bush and having found something to see, stop scouring the snow-blanketed landscape. By focusing their attention on one object at a time, the men can cross the snow without becoming hopelessly snow-blind or lost. In this way the problem of crossing a solid white terrain is overcome. To prevent headaches, watering eyes and blindness caused by the glare from snow, dark glasses are__________.A. indispensible B. usefulC. ineffective D. available
Many people believe the glare from snow causes snow-blindness. Yet, dark glasses or not, they find themselves suffering from headaches and watering eyes, and even snow-blindness, when exposed to several hours of "snow light". The United States Army has now determined that glare from snow does not cause snow- blindness in troops in a snow-covered country. Rather, a man's eyes frequently find nothing to focus on in a broad expanse of barren snow-covered terrain. So his gaze continually shifts and jumps back and forth over the entire landscape in search of something to look at. Finding nothing, hour after hour, the eyes never stop searching and the eyeballs become sore and the eye muscles ache. Nature offsets this irritation by producing more and fluid which covers the eyeball. The fluid covers the eyeball in increasing quantity until vision blurs,then is observed, and the result is total, even though temporary, snow-blindness. Experiments led the Army to a simple method of overcoming this problem. Scouts ahead of a main body of troops are trained to shake snow from evergreen bushes, creating a dotted line as they cross completely snow-covered landscape. Even the scouts themselves throw lightweight, dark colored objects ahead on which they too can focus. The men following can then see something. Their gaze is arrested. Their eyes focus on a bush and having found something to see, stop scouring the snow-blanketed landscape. By focusing their attention on one object at a time, the men can cross the snow without becoming hopelessly snow-blind or lost. In this way the problem of crossing a solid white terrain is overcome. The scouts shake snow from evergreen bushes in order to_________.A. give the men behind something to seeB. beautify the landscapeC. warm themselves in the coldD. prevent the men behind from losing their way
Many people believe the glare from snow causes snow-blindness. Yet, dark glasses or not, they find themselves suffering from headaches and watering eyes, and even snow-blindness, when exposed to several hours of "snow light". The United States Army has now determined that glare from snow does not cause snow- blindness in troops in a snow-covered country. Rather, a man's eyes frequently find nothing to focus on in a broad expanse of barren snow-covered terrain. So his gaze continually shifts and jumps back and forth over the entire landscape in search of something to look at. Finding nothing, hour after hour, the eyes never stop searching and the eyeballs become sore and the eye muscles ache. Nature offsets this irritation by producing more and fluid which covers the eyeball. The fluid covers the eyeball in increasing quantity until vision blurs,then is observed, and the result is total, even though temporary, snow-blindness. Experiments led the Army to a simple method of overcoming this problem. Scouts ahead of a main body of troops are trained to shake snow from evergreen bushes, creating a dotted line as they cross completely snow-covered landscape. Even the scouts themselves throw lightweight, dark colored objects ahead on which they too can focus. The men following can then see something. Their gaze is arrested. Their eyes focus on a bush and having found something to see, stop scouring the snow-blanketed landscape. By focusing their attention on one object at a time, the men can cross the snow without becoming hopelessly snow-blind or lost. In this way the problem of crossing a solid white terrain is overcome. When the eyes are sore, tears are produced to_________.A. clear the vision B. remedy snow-blindnessC. ease the irritation D. loosen the muscles
There are many stereotypes about the character of people in various parts of the United States．In the Northeast and Midwest,people are said to be closed and private．In the South and West,however,they are often thought of as being more open and hospitable．Ask someone from St．Louis where the nearest sandwich shop is,and he or she will politely give you directions．A New Yorker might eye you at first and after deciding it is safe to talk to you,might give you a rather unexpected explanation．A person from Georgia might be very kind about directing you and even suggest some different places to eat．A Texan just might take you to the place and treat you to lunch.American stereotypes are abundant．New Englanders are often thought of as being friendly and helpful．Southerners are known for their hospitality and warmth．People from the western part of the United States are often considered very outgoing．These differences in character can be traced to different factors such as climate,living conditions,and historical development.When travelling from place to place,Americans themselves are often surprised at the differing degrees of friendliness in the United States.The main idea of the passage is__.A.even Americans are surprised at the big differences among themselvesB.there are many differences in character in different parts of the USAC.there are many reason for the differencesD.stereotypes about people are not necessarily true
资料：When we see well，we do not think about our eyes very often. It is only when we cannot see perfectly that we realize how important our eyes are.People who are near-sighted can only see things that are very close to their eyes，Everything else seems blurry（=unclear）.Many people who do a lot of work，such as writing，reading and sewing become near-sighted.People who are far-sighted suffer from just the opposite problem. They can see things that are far away，but they have difficulty in reading a book unless they hold it at arm’s length. If they want to do much reading，they must get glasses，too.Other people do not see clearly because their eyes are not exactly the right shape. They have what is called astigmatism. This，too，can be corrected by glasses. Some people’s eyes become cloudy because of cataracts. Long ago these people often became blind. Now，however，it is possible to operate on the cataracts and remove them.Having two good eyes is important for judging distances. Each eye sees things from a slightly different angle. To prove this to yourself，look at an object out of one eye；Then look at the same object out of your other eye. You will find the object’s relation to the background and other things around it has changed. The difference between these two different eye views helps us to judge how far away an object is. People who have only one eye cannot judge distance as people with two eyes.People who suffer from astigmatism have______.A.a difficulty that can be corrected by an operationB.eyes that are not exactly the right shapeC.an eye difficulty that cannot be corrected by glassesD.one eye bigger than the other
资料： The poverty line is the minimum income that people need for an acceptable standard of living. People with incomes below the poverty line are considered poor. Economists study the causes of poverty in order to find solutions to the problem. As the general standard of living in the country rises, the poverty line does, too. Therefore, even with today’s relatively high standard of living, about 10 percent of the people in the United States are below the poverty line. However, if these people had stable jobs, they could have an acceptable standard of living. Economists suggest several reasons why poor people do not have jobs.For one thing, more than half of the poor people in the United States are not qualified to work. Over 40 percent of the poor. People are children. By law, children less than 16 years old cannot work in many industries. A large number of poor people are Old. Many companies do not hire people over 65 years old, the normal retirement age. Some poor adults do not look for jobs for a variety of personal reasons: they are sick, they do not have any motivation, they have family problems, or they do not believe that they can find a job. Other poor people look for a job but cannot find one. Many poor adults never went to high school. Therefore, when they look for jobs, they have few skills that they can offer. At the present time, the government thinks it can reduce poverty in the country in the following ways. First, if the national economy grows, businesses and industries hire more workers. Some of the poor who are qualified to look for jobs may find employment. Then they will no longer be below the poverty line. Second, if society invests in the poor, the poor will become more productive. If the government spends money on social programs, education, and training for poor people, the poor will have the skills to offer. Then it is more likely that they can find jobs. Finally, if the government distributes society's income differently, it raises some poor people above the poverty line. The government collects taxes from the non－poor and gives money to the poor. These payments to the poor are called welfare. In 1975 over 18 million people in the United States received welfare.Some economists are looking for better solutions to the poverty problem. However, at the present time, many people depend on welfare for a minimally acceptable standard of living.We may conclude from the passage that _______A.poor people are bound to go out of the poverty line if they have chances to do businessB.welfare will enable people to be richC.employment is the best solution to the poverty problemD.better solutions to the poverty problem are not found yet
资料：When we see well，we do not think about our eyes very often. It is only when we cannot see perfectly that we realize how important our eyes are.People who are near-sighted can only see things that are very close to their eyes，Everything else seems blurry（=unclear）.Many people who do a lot of work，such as writing，reading and sewing become near-sighted.People who are far-sighted suffer from just the opposite problem. They can see things that are far away，but they have difficulty in reading a book unless they hold it at arm’s length. If they want to do much reading，they must get glasses，too.Other people do not see clearly because their eyes are not exactly the right shape. They have what is called astigmatism. This，too，can be corrected by glasses. Some people’s eyes become cloudy because of cataracts. Long ago these people often became blind. Now，however，it is possible to operate on the cataracts and remove them.Having two good eyes is important for judging distances. Each eye sees things from a slightly different angle. To prove this to yourself，look at an object out of one eye；Then look at the same object out of your other eye. You will find the object’s relation to the background and other things around it has changed. The difference between these two different eye views helps us to judge how far away an object is. People who have only one eye cannot judge distance as people with two eyes.Having two eyes instead of one is particularly useful for______.A.looking over a wide areaB.seeing objects far awayC.judging distancesD.seeing at night
资料：When we see well，we do not think about our eyes very often. It is only when we cannot see perfectly that we realize how important our eyes are.People who are near-sighted can only see things that are very close to their eyes，Everything else seems blurry（=unclear）.Many people who do a lot of work，such as writing，reading and sewing become near-sighted.People who are far-sighted suffer from just the opposite problem. They can see things that are far away，but they have difficulty in reading a book unless they hold it at arm’s length. If they want to do much reading，they must get glasses，too.Other people do not see clearly because their eyes are not exactly the right shape. They have what is called astigmatism. This，too，can be corrected by glasses. Some people’s eyes become cloudy because of cataracts. Long ago these people often became blind. Now，however，it is possible to operate on the cataracts and remove them.Having two good eyes is important for judging distances. Each eye sees things from a slightly different angle. To prove this to yourself，look at an object out of one eye；Then look at the same object out of your other eye. You will find the object’s relation to the background and other things around it has changed. The difference between these two different eye views helps us to judge how far away an object is. People who have only one eye cannot judge distance as people with two eyes.The underlined word suffer in the third paragraph probably means______.A.feel painB.imagineC.are affected withD.experience
资料：When we see well，we do not think about our eyes very often. It is only when we cannot see perfectly that we realize how important our eyes are.People who are near-sighted can only see things that are very close to their eyes，Everything else seems blurry（=unclear）.Many people who do a lot of work，such as writing，reading and sewing become near-sighted.People who are far-sighted suffer from just the opposite problem. They can see things that are far away，but they have difficulty in reading a book unless they hold it at arm’s length. If they want to do much reading，they must get glasses，too.Other people do not see clearly because their eyes are not exactly the right shape. They have what is called astigmatism. This，too，can be corrected by glasses. Some people’s eyes become cloudy because of cataracts. Long ago these people often became blind. Now，however，it is possible to operate on the cataracts and remove them.Having two good eyes is important for judging distances. Each eye sees things from a slightly different angle. To prove this to yourself，look at an object out of one eye；Then look at the same object out of your other eye. You will find the object’s relation to the background and other things around it has changed. The difference between these two different eye views helps us to judge how far away an object is. People who have only one eye cannot judge distance as people with two eyes.When things far away seem indistinct， one is probably______.A.astigmaticB.far-sightedC.suffering from cataractsD.near-sighted
资料：When we see well，we do not think about our eyes very often. It is only when we cannot see perfectly that we realize how important our eyes are.People who are near-sighted can only see things that are very close to their eyes，Everything else seems blurry（=unclear）.Many people who do a lot of work，such as writing，reading and sewing become near-sighted.People who are far-sighted suffer from just the opposite problem. They can see things that are far away，but they have difficulty in reading a book unless they hold it at arm’s length. If they want to do much reading，they must get glasses，too.Other people do not see clearly because their eyes are not exactly the right shape. They have what is called astigmatism. This，too，can be corrected by glasses. Some people’s eyes become cloudy because of cataracts. Long ago these people often became blind. Now，however，it is possible to operate on the cataracts and remove them.Having two good eyes is important for judging distances. Each eye sees things from a slightly different angle. To prove this to yourself，look at an object out of one eye；Then look at the same object out of your other eye. You will find the object’s relation to the background and other things around it has changed. The difference between these two different eye views helps us to judge how far away an object is. People who have only one eye cannot judge distance as people with two eyes.We should take good care of our eyes______.A.even if we can see wellB.only when we cannot see perfectlyC.only when we realize how important our eyes areD.only when we can see well
共用题干The Dangers of Secondhand SmokeMost people know that cigarette smoking is harmful to their health.Scientific research shows that it causes many kinds of diseases.In fact,many people who smoke get lung cancer. However,Edward Gilson has lung cancer,and he has never smoked cigarettes.He lives with his wife Evelyn,who has smoked about a pack of cigarettes a day throughout their marriage.________(46)No one knows for sure why Mr. Gilson has lung cancer. Nevertheless,doctors believe that secondhand smoke may cause lung cancer in people who do not smoke because nonsmokers often breathe in the smoke from other people's cigarettes.________(47)The US Environmental Protection Agency reports that about 53,000 people die in the United States each year as a result of exposure to secondhand smoke.The smoke that comes from a lit cigarette contains many different poisonous chemicals.In the past, scientists did not think that these chemicals could harm a nonsmoker's health._________(48)They discovered that even nonsmokers had unhealthy amounts of these toxic chemicals in their bodies.As a matter of fact,almost all of us breathe tobacco smoke at times,whether we realize it or not. For example,we can not avoid secondhand smoke in restaurants,hotels and other public places.Even though many public places have nonsmoking areas,smoke flows in from the areas where smoking is permitted.It is even harder for children to avoid secondhand smoke._________(49)Research shows that chil- dren who are exposed to secondhand smoke are sick more often than children who live in homes where no one smokes and that the children of smokers are more than twice as likely to develop lung cancer when they are adults as are children of nonsmokers.The risk is even higher for children who live in homes where both parents smoke.People are becoming very aware of the dangers of secondhand smoke._________（50)__________（50）A:Recently,though,scientists changed their opinion after they studied a large group of nonsmokers.B:The Gilsons have been married for 35 years.C:This smoke is called secondhand smoke.D:However,secondhand smoke is dangerous to all people,old or young.E:As a result,they have passed laws which prohibit people from smoking in many public places.F: In the United States,nine million children under the age of five live in homes with at least one smoker.
In many societies of the world， we find a large number of people who speak more than one language. As a characteristic of societies， b（） inevitably results from the coming into contact of people with different cultures and different languages.
问答题Directions:In this section, there is one passage followed by a summary. Read the passage carefully and complete the summary below by choosing a maximum of three words from the passage to fill in the spaces 76-80. Remember to write the answers on the Answer Sheet. Questions 1-5 are based on the following passage. Headaches are a big problem. But they are not just a problem for the person suffering from the headache. They are a problem for society as well. Each year, millions of people suffer from severe headaches that keep them from doing their jobs. In fact, according to one estimate, headaches cost individuals and businesses more than $50 billion each year! This is one of the reasons research into headaches has become a worldwide effort. Although he did not know much about how headaches work, Hippocrates was the first doctor to find a way to treat them. Before 400 B.C., Hippocrates discovered that the bark from willow trees was useful in treating pain. He made a white powder from the tree’s bark and gave it to his patients. Hippocrates did not know it, but he was actually prescribing a natural chemical in willow bark called salicin. When a person eats salicin, the chemical is changed inside her or his body into salicylic acid. It turns out that salicylic acid is good for stopping pain, including headache, but it is bad for a person’s stomach. In the 1800s, a chemist in Germany changed the acid’s form a little to make it easier for people to take. This new form of the chemical was called acetylsalicylic acid, commonly known as aspirin today. Aspirin was used throughout most of the 1900s to treat headaches, but doctors had little idea about what really caused headaches. When doctors know the cause of a disease, they can find better ways to treat it. Therefore, as medical technology developed, doctors began to use the technology to learn more about the human brain and about headaches. Currently, doctors classify headaches into two general types: primary and secondary. A primary headache is a condition suffered as only the headache itself. On the other hand, a secondary headache is one caused by another condition. For example, someone who catches the flu may suffer from headaches along with other symptoms of the illness. Flu headaches are thus secondary headaches. For primary headaches, doctors have determined three possible causes. One kind of primary headache is caused by stress. Doctors usually call these tension headaches. Such headaches are characteristically felt on both sides of the head as a dull, steady pain.Another kind of primary headache is the migraine headache. Doctors believe these headaches are caused by reduced flow of blood to certain parts of the brain. A migraine sufferer usually feels intense pain on one side of the head. The sufferer also becomes sensitive to light and noise. If the migraine is severe, the sufferer may vomit repeatedly. The third kind of primary headache is known as the cluster headache. Cluster headaches typically occur around the same time each day for weeks or months at a time. The person suffering from this kind of headache usually feels pain on one side of her or his head, and the pain is centered around one of the person’s eyes. Doctors do not know much at present about cluster headaches, but they seem more common among men and could be related to alcohol or other things that affect a person’s blood flow. Using computers and more advanced medical equipment, doctors continue to learn more about what happens in the brain before and during headaches. Especially in the case of migraines, some doctors believe they have found the part of the brain that sets off the reaction for severe attacks. With this new insight into brain processes, doctors hope new ways will be discovered for stopping disabling headaches before they begin. Summary: Doctors knew a long time ago that the 1 from the willow trees could help people who felt pain. Hippocrates was the first doctor to change organic material into a powder and give it to his patients. But it was not until the 1800s that this natural drug was altered and became known as 2 . With the help of technology, doctors have now gained detailed insight into how the brain works and what happens when a person suffers from a headache. Through this research, headaches have been 3 primary and secondary headaches. There are three types of primary headaches: tension, migraine, and cluster headaches. Although not much is known about cluster headaches, doctors have been able to determine some of the things that 4 During a migraine attack, the sufferer may become 5 and noise.
单选题I do not advocate building the park near a jetport, which might make people to suffer from defective hearing.Amake people suffering from defective hearingBmake people suffer from defective hearingCmake people suffer defective hearingDmake people to suffer defective hearing