The average number of hours of sleep that an adult needs is ______.A. approximately six hoursB. around ten hoursC. about eight hoursD. not stated here
The average number of hours of sleep that an adult needs is ______.
A. approximately six hours
B. around ten hours
C. about eight hours
D. not stated here
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共用题干Sleep DeficitJudging from recent surveys,most experts in sleep behavior agree that there is virtually an epidemic（流行病）of sleepiness in the nation."I can't think of a single study that hasn't found Americans getting less sleep than they ought to,"says Dr.David.Even people who think they are sleeping enough would probably be better off with more rest.The beginning of our sleep-deficit（睡眠不足）crisis can be traced to the invention of the light bulb a century ago.From diary entries and other personal accounts from the 18th and 19th centuries,sleep scientists have reached the conclusion that the average person used to sleep about 9.5 hours a night."The best sleep habits once were forced on us,when we had nothing to do in the evening down on the farm,and it was dark."By the 1950s and 1960s,that sleep schedule had been reduced dramatically,to between 7.5 and 8 hours,and most people had to wake up to an alarm clock."People cheat on their sleep,and they don't even realize they're doing it,"says Dr.David."They think they're okay because they can get by on 6.5 hours, when they really need 7.5,8 or even more to feel ideally vigorous."Perhaps the most merciless robber of sleep,researchers say,is the complexity of the day.Whenever pressures from work,family,friends and community mount,many people consider sleep the least expensive item on his programme.In our society,you're considered dynamic if you say you only need 5;5 hours, sleep.If you've got to get 8.5 hours,people think you lack drive and ambition.To determine the consequences of sleep deficit,researchers have put subjects through a set of psycho-logical and performance tests requiring them,for instance,to add columns of numbers or recall a passage read to them only minutes earlier."We've found that if you're in sleep deficit,performance suffers,"says Dr.David."Short-term memory is weakened,as arc abilities to make decisions and to concentrate."People in the 18th and 19th centuries used to sleep about 9.5 hours a night because they had______.A:no drive and ambition B:the best sleep habitsC:no electric light D:nothing to do in the evening
共用题干Sleep DeficitJudging from recent surveys,most experts in sleep behavior agree that there is virtually an epidemic（流行病）of sleepiness in the nation."I can't think of a single study that hasn't found Americans getting less sleep than they ought to,"says Dr.David.Even people who think they are sleeping enough would probably be better off with more rest.The beginning of our sleep-deficit（睡眠不足）crisis can be traced to the invention of the light bulb a century ago.From diary entries and other personal accounts from the 18th and 19th centuries,sleep scientists have reached the conclusion that the average person used to sleep about 9.5 hours a night."The best sleep habits once were forced on us,when we had nothing to do in the evening down on the farm,and it was dark."By the 1950s and 1960s,that sleep schedule had been reduced dramatically,to between 7.5 and 8 hours,and most people had to wake up to an alarm clock."People cheat on their sleep,and they don't even realize they're doing it,"says Dr.David."They think they're okay because they can get by on 6.5 hours, when they really need 7.5,8 or even more to feel ideally vigorous."Perhaps the most merciless robber of sleep,researchers say,is the complexity of the day.Whenever pressures from work,family,friends and community mount,many people consider sleep the least expensive item on his programme.In our society,you're considered dynamic if you say you only need 5;5 hours, sleep.If you've got to get 8.5 hours,people think you lack drive and ambition.To determine the consequences of sleep deficit,researchers have put subjects through a set of psycho-logical and performance tests requiring them,for instance,to add columns of numbers or recall a passage read to them only minutes earlier."We've found that if you're in sleep deficit,performance suffers,"says Dr.David."Short-term memory is weakened,as arc abilities to make decisions and to concentrate."The word"subjects"(Line 1,Para 4)refers to______.A:the performance tests used in the study of sleep deficitB:special branches of knowledge that are being studiedC:people whose behavior or reactions are being studiedD:the psychological consequences of sleep deficit
共用题干第二篇Sleep DeficitJudging from recent surveys,most experts in sleep behavior agree that there is virtually an epidemic（流 行病）of sleepiness in the nation."I can't think of a single study that hasn't found Americans getting less sleep than they ought to,"says Dr. David.Even people who think they are sleeping enough would probably be better off with more rest.The beginning of our sleep-deficit (睡眠不足）crisis can be traced to the invention of the light bulb a century ago.From diary entries and other personal accounts from the 18th and 19th centuries,sleep scien- tists have reached the conclusion that the average person used to sleep about 9.5 hours a night."The best sleep habits once were forced on us,when we had nothing to do in the evening down on the farm,and it was dark."By the 1950s and 1960s,that sleep schedule had been reduced dramatically,to between 7.5 and 8 hours,and most people had to wake up to an alarm clock."People cheat on their sleep,and they don't even realize they're doing it,"says Dr. David."They think they're okay because they can get by on 6.5 hours, when they really need 7.5,eight or even more to feel ideally vigorous.Perhaps the most merciless robber of sleep,researchers say,is the complexity of the day.Whenever pressures from work,family,friends and community mount,many people consider sleep the least expensive item on his programme.In our society,you're considered dynamic if you say you only need 5.5hours' sleep.If you'ye got to get 8.5 hours,people think you lack drive and ambition.To determine the consequences of sleep deficit,researchers have put subjects through a set of psycho- logical and performance tests requiring them,for instance,to add columns of numbers or recall a passage read to them only minutes earlier."We'ye found that if you're in sleep deficit,performance suffers,"says Dr. David."Short-term memory is weakened,as are abilities to make decisions and to concentrate."Many Americans believe that________.A:sleep is the first thing that can be sacrificed when one is busyB:they need more sleep to cope with the complexities of everyday lifeC:to sleep is something one can do at any time of the dayD:enough sleep promotes people's drives and ambition
共用题干Sleep DeficitJudging from recent surveys,most experts in sleep behavior agree that there is virtually an epidemic（流行病）of sleepiness in the nation."I can't think of a single study that hasn't found Americans getting less sleep than they ought to,"says Dr.David.Even people who think they are sleeping enough would probably be better off with more rest.The beginning of our sleep-deficit（睡眠不足）crisis can be traced to the invention of the light bulb a century ago.From diary entries and other personal accounts from the 18th and 19th centuries,sleep scientists have reached the conclusion that the average person used to sleep about 9.5 hours a night."The best sleep habits once were forced on us,when we had nothing to do in the evening down on the farm,and it was dark."By the 1950s and 1960s,that sleep schedule had been reduced dramatically,to between 7.5 and 8 hours,and most people had to wake up to an alarm clock."People cheat on their sleep,and they don't even realize they're doing it,"says Dr.David."They think they're okay because they can get by on 6.5 hours, when they really need 7.5,8 or even more to feel ideally vigorous."Perhaps the most merciless robber of sleep,researchers say,is the complexity of the day.Whenever pressures from work,family,friends and community mount,many people consider sleep the least expensive item on his programme.In our society,you're considered dynamic if you say you only need 5;5 hours, sleep.If you've got to get 8.5 hours,people think you lack drive and ambition.To determine the consequences of sleep deficit,researchers have put subjects through a set of psycho-logical and performance tests requiring them,for instance,to add columns of numbers or recall a passage read to them only minutes earlier."We've found that if you're in sleep deficit,performance suffers,"says Dr.David."Short-term memory is weakened,as arc abilities to make decisions and to concentrate."According to Dr.David,Americans______.A:are ideally vigorous even under the pressure of lifeB:often neglect the consequences of sleep deficitC:don't know how to relax themselves properlyD:can't get by on 6.5 hours of sleep
共用题干第三篇Judging from recent surveys,most experts in sleep behavior agree that it is virtually an epidemic of sleepiness in the nation."I can't think of a single study that hasn't found Americans getting less sleep than they ought to,"says Dr. David.Even people who think they are sleeping enough would probably be better off with more rest.The beginning of our sleep-deficit crisis can be traced to the invention of the light bulb a century ago.From diary entries and other personal accounts from the 18th and 19th centuries,sleep scientists have reached the conclusion that the average person used to sleep about 9.5 hours a night. "The best sleep habits once were forced on us,when we had nothing to do in the evening down on the farm,and it was dark." By the 1950s and 1960s,that sleep schedule had been reduced dramatically,to between 7.5 and 8 hours,and most people had to wake to an alarm clock."People cheat on their sleep,and they don't even realize they're doing it,"says Dr. David."They think they're okay because they can get by on 6.5 hours,when they really need 7.5,8 or even more to feel ideally vigorous.""Perhaps the most merciless robber of sleep,"researchers say,"is the complexity of the day." Whenever pressures from work,family,friends and community mount,many people consider sleep the least expensive item on his program."In our society,you're considered dynamic if you say you only need 5.5 hours' sleep.If you've got to get 8.5 hours,people think you lack drive and ambition."To determine the consequences of sleep deficit,researchers have put subjects through a set of psychological and performance tests requiring them,for instance,to add columns of numbers or recall a page read to them only minutes earlier."We've found that if you're in sleep deficit,performance suffers,"says Dr. David."Short-term memory is weakened,as are abilities to make decision and to concentrate."According to Dr. David,Americans___________.A: are ideally vigorous even under the pressure of lifeB:often neglect the consequences of sleep deficitC:do not know how to relax themselves properlyD:can get by on 6.5 hours of sleep
共用题干第三篇Judging from recent surveys,most experts in sleep behavior agree that it is virtually an epidemic of sleepiness in the nation."I can't think of a single study that hasn't found Americans getting less sleep than they ought to,"says Dr. David.Even people who think they are sleeping enough would probably be better off with more rest.The beginning of our sleep-deficit crisis can be traced to the invention of the light bulb a century ago.From diary entries and other personal accounts from the 18th and 19th centuries,sleep scientists have reached the conclusion that the average person used to sleep about 9.5 hours a night. "The best sleep habits once were forced on us,when we had nothing to do in the evening down on the farm,and it was dark." By the 1950s and 1960s,that sleep schedule had been reduced dramatically,to between 7.5 and 8 hours,and most people had to wake to an alarm clock."People cheat on their sleep,and they don't even realize they're doing it,"says Dr. David."They think they're okay because they can get by on 6.5 hours,when they really need 7.5,8 or even more to feel ideally vigorous.""Perhaps the most merciless robber of sleep,"researchers say,"is the complexity of the day." Whenever pressures from work,family,friends and community mount,many people consider sleep the least expensive item on his program."In our society,you're considered dynamic if you say you only need 5.5 hours' sleep.If you've got to get 8.5 hours,people think you lack drive and ambition."To determine the consequences of sleep deficit,researchers have put subjects through a set of psychological and performance tests requiring them,for instance,to add columns of numbers or recall a page read to them only minutes earlier."We've found that if you're in sleep deficit,performance suffers,"says Dr. David."Short-term memory is weakened,as are abilities to make decision and to concentrate."The word"subjects"(line 1,Para.4)refers to__________.A:the performance tests used in the study of sleep deficitB:special branches of knowledge that are being studiedC:people whose behaviors or reactions are being studiedD:the psychological consequences of sleep deficit
共用题干第三篇Judging from recent surveys,most experts in sleep behavior agree that it is virtually an epidemic of sleepiness in the nation."I can't think of a single study that hasn't found Americans getting less sleep than they ought to,"says Dr. David.Even people who think they are sleeping enough would probably be better off with more rest.The beginning of our sleep-deficit crisis can be traced to the invention of the light bulb a century ago.From diary entries and other personal accounts from the 18th and 19th centuries,sleep scientists have reached the conclusion that the average person used to sleep about 9.5 hours a night. "The best sleep habits once were forced on us,when we had nothing to do in the evening down on the farm,and it was dark." By the 1950s and 1960s,that sleep schedule had been reduced dramatically,to between 7.5 and 8 hours,and most people had to wake to an alarm clock."People cheat on their sleep,and they don't even realize they're doing it,"says Dr. David."They think they're okay because they can get by on 6.5 hours,when they really need 7.5,8 or even more to feel ideally vigorous.""Perhaps the most merciless robber of sleep,"researchers say,"is the complexity of the day." Whenever pressures from work,family,friends and community mount,many people consider sleep the least expensive item on his program."In our society,you're considered dynamic if you say you only need 5.5 hours' sleep.If you've got to get 8.5 hours,people think you lack drive and ambition."To determine the consequences of sleep deficit,researchers have put subjects through a set of psychological and performance tests requiring them,for instance,to add columns of numbers or recall a page read to them only minutes earlier."We've found that if you're in sleep deficit,performance suffers,"says Dr. David."Short-term memory is weakened,as are abilities to make decision and to concentrate."People in the 18th and 19th centuries used to sleep about 9.5 hours a night because they had__________.A:no drive and ambitionB:no electric lightingC:the best sleep habitsD:a lot to do the next day
共用题干第二篇Sleep DeficitJudging from recent surveys,most experts in sleep behavior agree that there is virtually an epidemic（流 行病）of sleepiness in the nation."I can't think of a single study that hasn't found Americans getting less sleep than they ought to,"says Dr. David.Even people who think they are sleeping enough would probably be better off with more rest.The beginning of our sleep-deficit (睡眠不足）crisis can be traced to the invention of the light bulb a century ago.From diary entries and other personal accounts from the 18th and 19th centuries,sleep scien- tists have reached the conclusion that the average person used to sleep about 9.5 hours a night."The best sleep habits once were forced on us,when we had nothing to do in the evening down on the farm,and it was dark."By the 1950s and 1960s,that sleep schedule had been reduced dramatically,to between 7.5 and 8 hours,and most people had to wake up to an alarm clock."People cheat on their sleep,and they don't even realize they're doing it,"says Dr. David."They think they're okay because they can get by on 6.5 hours, when they really need 7.5,eight or even more to feel ideally vigorous.Perhaps the most merciless robber of sleep,researchers say,is the complexity of the day.Whenever pressures from work,family,friends and community mount,many people consider sleep the least expensive item on his programme.In our society,you're considered dynamic if you say you only need 5.5hours' sleep.If you'ye got to get 8.5 hours,people think you lack drive and ambition.To determine the consequences of sleep deficit,researchers have put subjects through a set of psycho- logical and performance tests requiring them,for instance,to add columns of numbers or recall a passage read to them only minutes earlier."We'ye found that if you're in sleep deficit,performance suffers,"says Dr. David."Short-term memory is weakened,as are abilities to make decisions and to concentrate."It can be infered from this passage that one should sleep as many hours as is necessary to_________.A:improve one’s memory dramaticallyB:be considered dynamic by other peopleC:maintain one’s daily scheduleD:feel energetic and perform adequately
共用题干第三篇Judging from recent surveys,most experts in sleep behavior agree that it is virtually an epidemic of sleepiness in the nation."I can't think of a single study that hasn't found Americans getting less sleep than they ought to,"says Dr. David.Even people who think they are sleeping enough would probably be better off with more rest.The beginning of our sleep-deficit crisis can be traced to the invention of the light bulb a century ago.From diary entries and other personal accounts from the 18th and 19th centuries,sleep scientists have reached the conclusion that the average person used to sleep about 9.5 hours a night. "The best sleep habits once were forced on us,when we had nothing to do in the evening down on the farm,and it was dark." By the 1950s and 1960s,that sleep schedule had been reduced dramatically,to between 7.5 and 8 hours,and most people had to wake to an alarm clock."People cheat on their sleep,and they don't even realize they're doing it,"says Dr. David."They think they're okay because they can get by on 6.5 hours,when they really need 7.5,8 or even more to feel ideally vigorous.""Perhaps the most merciless robber of sleep,"researchers say,"is the complexity of the day." Whenever pressures from work,family,friends and community mount,many people consider sleep the least expensive item on his program."In our society,you're considered dynamic if you say you only need 5.5 hours' sleep.If you've got to get 8.5 hours,people think you lack drive and ambition."To determine the consequences of sleep deficit,researchers have put subjects through a set of psychological and performance tests requiring them,for instance,to add columns of numbers or recall a page read to them only minutes earlier."We've found that if you're in sleep deficit,performance suffers,"says Dr. David."Short-term memory is weakened,as are abilities to make decision and to concentrate."Many Americans believe that__________.A:sleep is the first thing that can be sacrificed when one is busyB:they need more sleep to cope with the complexities of everyday lifeC:to sleep is something one can do at any time of the dayD:enough sleep promotes people's drive and ambition
共用题干第三篇Judging from recent surveys,most experts in sleep behavior agree that it is virtually an epidemic of sleepiness in the nation."I can't think of a single study that hasn't found Americans getting less sleep than they ought to,"says Dr. David.Even people who think they are sleeping enough would probably be better off with more rest.The beginning of our sleep-deficit crisis can be traced to the invention of the light bulb a century ago.From diary entries and other personal accounts from the 18th and 19th centuries,sleep scientists have reached the conclusion that the average person used to sleep about 9.5 hours a night. "The best sleep habits once were forced on us,when we had nothing to do in the evening down on the farm,and it was dark." By the 1950s and 1960s,that sleep schedule had been reduced dramatically,to between 7.5 and 8 hours,and most people had to wake to an alarm clock."People cheat on their sleep,and they don't even realize they're doing it,"says Dr. David."They think they're okay because they can get by on 6.5 hours,when they really need 7.5,8 or even more to feel ideally vigorous.""Perhaps the most merciless robber of sleep,"researchers say,"is the complexity of the day." Whenever pressures from work,family,friends and community mount,many people consider sleep the least expensive item on his program."In our society,you're considered dynamic if you say you only need 5.5 hours' sleep.If you've got to get 8.5 hours,people think you lack drive and ambition."To determine the consequences of sleep deficit,researchers have put subjects through a set of psychological and performance tests requiring them,for instance,to add columns of numbers or recall a page read to them only minutes earlier."We've found that if you're in sleep deficit,performance suffers,"says Dr. David."Short-term memory is weakened,as are abilities to make decision and to concentrate."It can be concluded from the passage that one should sleep as many hours as is necessary to________.A:improve one's memory dramaticallyB:be considered dynamic by other peopleC:maintain one's daily scheduleD:feel energetic and perform adequately