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科目: 来源:同步题 题型:阅读理解

阅读理解。

     A new study has found no evidence that sunscreen, commonly used to reduce the
risk of skin cancer, actually increases the risk.
     Researchers from the Umversity of Iowa based their findings on a revicw of 18 earlier
studies that looked at the association between sunscreen use and melanoma(黑素瘤 ).
They said that they found flaws in studies that had reported associations between sunscreen
use and higher risk of melanoma.
     Most health experts believe that by protecting the skin from the harmful effects of
the sun, sunscreen helps prevent skin cancer, which is increasing in incidence (发生率)
faster than any other cancer in the United States.
     But questions have been raised about sunscreen and whether it may have the opposite
effect, perhaps by allowing people to remain exposed to the sun longer without burning.
     The researchers said that among the problems with some earlier studies is that they
often failed to take into account that those people most at risk for skin cancer-people
with fair skin and freckles(雀斑) ,for example-are more likely to use sunscreen. As a
result , it may appear that sunscreen users get cancer more often.
     The studies , which generally relied on volunteers to recall their sunscreen use,were
also unable to prove how well the products had been applied , Said the new study.

1. Theunderlinedword" flaws "inthe2ndparagraphmost probably means ________.
A. evidences
B. facts
C. faults
D. failures
2. People with fair skin and freckles ________.
A. seldom use sunscreen
B. are more in danger of skin cancer
C. can be free from the harm of the sun
D. often expose themselves to the sun
3. We can learn from the passage that _______.
A. sunscreen users get skin cancer more often
B. the volunteers have proved the effect of sunscreen
C. the new study was based on the experiences of volunteers
D. the number of skin cancer patients is increasing in America
4. Which of the following can be the best title for this passage?
A. Sunscreen to Prevent Skin Cancer
B. Sunscreen to Increase Skin Cancer
C. Skin Cancer Caused by Sunscreen
D. Skin Cancer Caused by Freckles

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科目: 来源:安徽省模拟题 题型:阅读理解

认真阅读下列短文,并根据所读内容在文章后表格中的空格里填入一个最恰当的单词.
注意:每个空格只填1个单词.
     People who enjoy a dream-filled sleep are better at recalling information and making links between facts when waking. But recharging with a shallow (小睡) offers no such mental improvement, the research
suggests. The results of the study added to the growing body of evidence that Rapid Eye Movement (REM) sleep is very important to the brain's ability to form strong memories.
     An average night's rest includes four or five spells of REM sleep, but these bursts tend to be lengthier towards the end of the night. This means adults getting less than the recommended seven to eight hours a night -- and therefore inadequate REM sleep -- may be damaging their mind's ability to memorize: Although REM sleep is not classified as a type of deep sleep, it is only reached after the brain has passed through deep
sleep stages.
     In the recent study, participants were shown groups of three words and asked to find another word that can be associated with all three words. They were tested once in the morning and then given the same task
again in the afternoon. In between, some were allowed a nap with REM sleep, some a nap without REM
sleep, while the others had a quiet rest period. The quiet rest and non-REM sleep groups didn't improve, but the REM sleep group improved on their morning performance by an average of almost 40 per cent. Dr Sara Mednick, a sleep researcher at the University of California who led the study, believes the formation of
connections between previously unassociated information in the brain occurs during REM sleep.
     It is believed that sleep acts as a sort of mental filing system, enabling the brain to sort relevant
information from useless information. This process may take place as memories are removed hem one art of the brain to others. 
Title REM Sleep (1) ______  Memory  
The result of the
study
Rapid Eye Movement sleep is of great importance to the brain's ability to (2) ______ memories.
The (3) ____ of the study ◆ (4) ______ were required to think of another word associated with all three words.
◆The same task was given to participants (5) ______ a day.
◆ The quiet rest and non-REM sleep groups showed no  (6) ______.
◆ The REM sleep group (7) ______ well by an average of almost 40 per cent.
Dr Sara Mednick's (8)_____ Connections between previous unassociated information in the brain are (9) ______
during REM sleep
Conclusion Sleep acts as a sort of mental filing system, enabling the brain to abandon useless information and keep the (10) ______ information.

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科目: 来源:同步题 题型:阅读理解

阅读理解
     A recent study conducted by researchers at the University of Michigan ' s Center for Human Growth
and Development shows that children aged 9 t0 12 who sleep less than nine hours a night can have real
problems with gaining weight.
     Dr.Julie Lumeng, lead author of the report said, " Many children aren't getting enough sleep , which
may not only make them annoyed or prevent them from being active and ready to learn at
school,but also lead to a higher risk of being overweight. " Reuters reports.
     She also said that children who sleep more than 10 hours a night are more willing to play and consume
their energy , rather than staying in bed or watching TV as their tired fellows do.
      It is also said that hormonal(荷尔蒙) changes brought on by a lack of sleep can lead to an increased
appetite.
     The study focused on 785 children aged 9 to 12 from 10 different states and it confirmed that 18%
were overweight by the time they reached the sixth grade. Children who do not sleep nine or more hours
a night when they are in the third grade are more likely to gain weight by the time they are in the sixth
grade.
     The conclusion of the study is very simple :
     "Our findings also provide additional support for policies that approve of later school start times. The
very early school start times for US children have raised concerns in the medical community because of
their apparent  negative effects  on  sleep  duration(廷续性) and , consequently, children's  general
academic and behavioral functioning , " Reuters reports.
     According to National Sleep Foundation, children in first grade should sleep from 10 to 12 hours a
night.
     Dr. Julie Lumeng' s report was published in the journal of the American Academy of Pediatrics (小
儿辩 ) in November.
1. According to Dr.  Julie Lumeng, if children lack sleep, they _____.
A. fall asleep during the lecture
B. become unhappy and inactive
C. are ready to leam their lessons
D. are active in doing school work
2. Children who get enough sleep seem more active because_____.    
A. they experience a pleasant time
B. they are better at playing sports
C. they have enough energy to use
D. their personalities are more outgoing
3. What does the author want to argue in Paragraph 5?
A. Students in the third grade are more likely to gain weight.
B. A lack of sleep is associated with weight gain.
C. Less than one fifth of children are overweight.
D. The longer they sleep , the heavier they become.
4. Why has medical community showed concerns about US children ?
A. Because US children traditionally get up very late.
B. Because many students complain of too long school hours.
C. Because later school start times may affect children physically.
D. Because a lack of sleep creates harmful effects on children.
5. What is the best title for the text?  
A. Lack of Sleep Leads to Childhood Overweight
B. A Recent Study on Health Problem
C. A Danger to Children's Health
D. Sleep Time and Overweight

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科目: 来源:同步题 题型:阅读理解

阅读理解

     Do you want to live another 100 years or more? Some experts say that scientific advances will one
day enable humans to last tens of years beyond what is now seen as the natural limit of the human life
span.
      "I think we are knocking at the door of immortality(永生) , " said  Michael  Zey, a  Montclair State
University business professor and author of two books on the future. "I think by 2075 we will see it and
that's a conservative estimate(保守的估计)."
      At the conference in San Francisco, Donald Louria, a professor at New Jersey Medical School in
Newark said advances in using genes as well as nanotechnology(纳米技术) make it likely that humans
will live in the future beyond what has been possible in the past. "There is a great push so that people can
live from 120 to 180 years," he said. "Some have suggested that there is no limit and that people could
live to 200 or 300 or 500 years.
     However,many scientists who specialize in ageing are doubtful about it and say the human body is just
not designed to last past about 120 years. Even with healthier lifestyles and less disease,they say the
failure of the brain and organs will finally lead all humans to death.
     Scientists also differ on what kind of life the super aged might live. "lt remains to be seen if you pass
120 ,you know; could you be healthy enough to have good quality of life?" said Leonard Poon, director
 of the University of Georgia Gerontology Centre. "At present people who could get to that point are not
in good health at all. "

1. By saying " we are knocking at the door of immortality" , Michael Zey means ___________.  
A. they believe that there is no limit of living
B. they are sure to find the truth about long living
C. they have got some ideas about living forever
D. they are able to make people live past the present life span
2. Donald Louria's attitude towards long living is that_______.  
A .people can live from 120 to 180
B. it is still doubtful how long humans can live
C. the human body is designed to last past about 120 years
D. it is possible for humans to live longer in the future
3. The underlined word in"it"( in Paragraph 4)refers to_______.  
A  a great push
B. the idea of living beyond the present life span
C. the idea of living from 200 to 300 years
D. the conservative estimate
4. What would be the best title for this text? 
A. Living Longer or Not
B. Science , Technology and Long Living
C. No Limit for Human Life
D. Healthy Lifestyle and Long Living

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科目: 来源:同步题 题型:阅读理解

阅读理解
      A rainforest is an area covered by tall trees with the total high rainfall spreading quite equally through
the year and the temperature rarely dipping below 16℃. Rainforests have a great effect on the world
environment because they can take in heat from the sun and adjust the climate.
     Without the forest cover, these areas would reflect more heat into the atmosphere, warming the rest
of the world. Losing the rainforests may also influence wind and rainfall patterns, potentially causing
certain natural disasters all over the world.
     In the past hundred years, humans have begun destroying rainforests in search of three major
resources (资源):land forcrops, wood for paper and other products ,land for raising farm animals. This
action affects the environment as a whole. For example, a lot of carbon dioxide (二氧化碳) in the air
comes from burning the rainforests. People obviously have a need for the resources we gain from cutting
trees but we will suffer much more than we will benefit.
    There are two main reasons for this. Firstly, when people cut down trees , generally they can only use
the land for a year or two. Secondly, cutting large sections of rainforests may provide a good supply of
wood right now,but in the long run it actually reduces the world's wood supply.
     Rainforests are often called the world's drug store. More than 25% of the medicines we use today
come from plants in rainforests. However, fewer than l% of rainforest plants have been examined for
their medical value. It is extremely likely that our best chance to cure diseases lies somewhere in the
world's shrinking rainforests.
1. Rainforests can help to adjust the climate because they_________.  
A.reflect more heat into the atmosphere
B. bring about high rainfall throughout the world
C. rarely cause the temperature to drop lower than 16℃
D. reduce the effect of heat from the sun on the earth
2. What  does  the  word "this" underlined in the third paragraph refer to?  
A. We will lose much more than we can gain.
B. Humans have begun destroying rainforests.
C. People have a strong desire for resources.
D. Much carbon dioxide comes from buming rainforests.
3. It can be inferred from the text that____________.   
A. we can get enough resources without rainforests
B. there is great medicine potential in rainforests
C. we will grow fewer kinds of crops in the gained land
D. the level of annual rainfall affects wind patterns
4. What might be the best title for the text?  
A. How to Save Rainforests
B. How to Protect Nature
C. Rainforests and the Environment
D. Rainforests and Medical Development

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科目: 来源:同步题 题型:阅读理解

阅读理解。
     A volcanic eruption in Iceland has sent ash across northern Europe. Airlines have stopped or
changed the flights across the Atlantic Ocean, leaving hundreds of passengers stuck in airports.
     Grimsvom is one of the largest and most active volcanoes in Europe. What makes Grimsvom
different is that it lies under a huge glacier(冰川) of ice up to 12 meters thick. The hot volcano
heats up the ice above it, which then forms a layer(层)of water between the glacier and the volcano.
This layer of water puts pressure on the volcano, keeping it stable. As the water flows out from under
the glacier, the pressure lifts. The lava(岩浆) from the volcano then comes up to the surface. This is
exactly what happened today.
     Now, airlines have to make changes to their flights so as not to fly through the clouds of volcanic
ash. According to KLM,one of Europe's biggest airlines, airplanes cannot go under the cloud or over
it. Going through the cloud can result in ash getting stuck in the airplane's engines, causing damage to
the plane.
     The eruption has also caused problems for animals in Iceland. The volcano left ash and sharp
glasslike rocks all over the countryside. Farmers are keeping their animals inside to stop them from
eating ashcovered grass or the sharp object.  
1.What makes Grimsvom different from other volcanoes?  
A.It is below ice.
B.It lies under the sea.
C.It is the largest volcano.
D.Its lava affects the airlines.  
2.What keeps Grimsvom still?  
A.The slow flow of water.
B.The low water temperature.  
C.The thick glacier.
D.The water pressure.  
3.Which of the following is the result of the volcanic eruption?
A.People stop traveling in Europe.
B.Airlines suffer from the loss of planes.  
C.It becomes dangerous for animals to eat outside.
D.Farmers have lost many of their animals.  
4.This text is most probably taken from________.
A.a research paper
B.a newspaper report
C.a class presentation
D.a geography textbook

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科目: 来源:模拟题 题型:阅读理解

阅读理解。
     In only two decades Asian Americans have become the fastest- growing US minority. As their children
began moving up through the nation's schools, it became clear that a new kind of culture was coming out.
Their achievements are made in the nation's best universities, where mathematics, science and engineering
departments have taken on a decidedly Asian character. This special liking for mathematics and science is
partly explained by the fact that Asian-American students who began their education abroad arrived in the
US with a solid grounding in mathematics but little or no knowledge of English. They are also influenced by
the promise of a good job after college. Asians feel there will be less unfair treatment in areas like mathematics
and science because they will be judged more objectively (客观). And the money spent on education is more
immediately returned in something like engineering than with an arts degree.
     Most Asian-American students owe their success to the influence of parents who are determined that their
children should take full advantage of what the American educational system has to offer. An effective measure
of parental attention is homework. Asian parents spend more time with their children than American parents
do, and it helps. Many researchers also believe there is something in Asian culture, such as family value, the
importance of education and so on that lead to their success.
     Both explanations for academic success worry Asian Americans because of fears that they could cause
the native Americans' unhappiness. Many can remember when Chinese, Japanese and Filipino immigrants (移
民) were unequally treated because of social separation. Indeed, it was not until 1952 that laws were laid down
giving all Asian immigrants the right to citizenship.
1. Few Asian-American students major in human sciences mainly because _____.
A. they are afraid they might meet with unfair judgment in these areas
B. there is a wide difference between Asian and Western cultures
C. they know little about American cultures and Western cultures
D. their English is not good enough
2. Asian-Americans prefer something like engineering to an arts degree because _____.
A. people majoring in engineering are respected
B. people with an arts degree are looked down upon
C. they can't find a job with an arts degree
D. they can earn more money after graduation
3. While making great achievements at college, Asian-American students _____.
A. are afraid that their.academic successes take on a strong Asian character
B. still worry about unfair treatment in society
C. generally feel it a shame to have to depend on their parents
D. feel they are mistreated because of limited knowledge of English
4. According to the passage, the major factors determining the success of Asian-Americans are _____.
A. Asian culture and the American educational system
B. Asian culture and a solid base in basic mathematics
C. hard work and parental help
D. hard work and a limited knowledge of English

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科目: 来源:0113 期中题 题型:完形填空

Close test.
     Not long ago, the only time you could see a robot was when you were reading a novel or watching a movie
such as Star Wars. Today,   1   a lot of things in science stories have been science facts. Robots are starting
to   2   in our everyday lives. These robots have different sizes, shapes and colors. But they all have the same   3   of man-made "  4  ". Leading the robot revolution (革命) are industrial robots that work in factories.
Industrial robots can do different kinds of jobs that are often   5   and sometimes dangerous. Robots are also
coming to American homes, though not as quickly as they are entering   6  . These robots aren't as friendly
and   7   as those you saw in Star Wars. But, their makers say, today's home robots "walk" and sense objects
in their own way. They even   8   objects though they may sometimes drop. Well, nobody is   9  .
     We may  10  home robots today, but some day they may see and hear  11  than humans do. We  12  can
only see certain wave lengths of light and hear certain  13 . That's because the  14  of our eyes and ears are
  15 . Robots, however, need not have the same limits  16  we have.
     Robots may also be  17  wit devices (装置) that  18  information humans can't. However, to understand 
 19  their sensing devices pick up is a hard job.
     Remember, man-made brains  20  information, including all kinds of data, as zeroes and ones.
     Imagine the difficulty in trying to explain to a robot what a football looks like-using only zeroes and ones.
(     )1. A. however    
(     )2. A. come       
(    )3. A. variety   
(     )4. A. muscle     
(     )5. A.  surprising 
(     )6. A. homes     
(     )7. A. certain   
(     )8. A. carry     
(     )9. A. wonderful  
(     )10. A. play jokes on          
(     )11. A. worse     
(     )12. A. fellows   
(     )13. A. noise     
(     )14. A. sight     
(     )15. A. enough     
(     )16. A. as        
(     )17. A. given     
(     )18. A. pick out   
(     )19. A. how       
(     )20. A. deal       
B. whenever  
B. appear   
B. dozen   
B. body    
B. boring   
B. factories 
B. pleasing  
B. forget   
B. excellent 
B. make fun of            
B. faster   
B. humans   
B. voice   
B. length   
B. endless  
B. since  
B. equipped  
B. pick up  
B. where   
B. handle   
C. on the other hand 
C. enter         
C. score     
C. brain       
C. pleasant        
C. schools    
C. bright       
C. remember        
C. happy       
C. laugh at    
C. better       
C. beings         
C. sounds     
C. distance        
C. limited      
C. for       
C. sent           
C. send up      
C. what       
C. seek        
D. in other words      
D. raise               
D. type             
D. appearance         
D. exciting            
D. offices          
D. foolish            
D. choose              
D. perfect           
D. have fun with                     
D. sooner             
D. friends             
D. speeches       
D. ability             
D. hopeful           
D. while            
D. applied             
D. send out          
D. which            
D. provide          

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科目: 来源:陕西省模拟题 题型:阅读理解

阅读理解。
     Attractive fathers do not pass their looks onto their sons but they will hand their good looks down to their
daughters, research shows.
     In a study of family photographs, Professor David Perrett and Elisabeth Cornwell-now at the University of
Colorado have found that while both father and mother can influence the attractiveness of their daughters, the
couple's good looks do not necessarily contribute to the attractiveness of their son as an adult. Handsome men
with masculine (阳刚的) looks are likely to pass on masculine features, but not facial attractiveness.
     The theory suggests it is not unusual for attractive parents to produce a beautiful daughter while failing to
pass on the same good looks to a son.
     While many celebrity mothers produce beautiful daughters-such as Goldie Hawn and her daughter Kate
Hudson or Jerry Hall and her daughter Georgia-the same is not necessarily true of celebrity fathers. Sean
Stewart, the son of Rod Stewart and his first wife Alan, would probably be judged less attractive than his model
sister Kimberly. "We can't see a strong relationship between the parents' attractiveness and the sons. If the
parents are supermodels, their daughters will be lookers," Perrett said.
     Prof Perrett said it has previously been suggested that a woman could increase her own reproductivets (繁
殖的) success by choosing a good-looking man whose genes would be passed onto male children. But the new
study, published in the current edition of the journal Animal Behaviour, disagrees with the theory.
     He said:"When we looked at women's faces, we found clear evidence that attractiveness passed from both
father and mother to daughter. For the male line, we find that facial masculinity follows the rule 'like father like
son'. Masculine dads have masculine sons. But we did not find any evidence that facial attractiveness is passed
from father to son."
1. Which of the followings is TRUE according to the passage?
[     ]
A. Father and mother can influence the attractiveness of their children.
B. Handsome fathers with masculine looks will not pass on masculine features.
C. There is a strong relationship between the parents' attractiveness and the daughters.
D. If the parents are supermodels, their sons will be good-looking.
2. What does the word "lookers" in the fourth paragraph most probably mean?
[     ]
A. On-lookers.
B. Models.
C. Beauties.
D. Passers-by.
3. How many celebrity families are mentioned in the passage?
[     ]
A. Three.
B. One.
C. Two.
D. Four.
4. The passage is most likely to be found in a book about _____.
[     ]
A. popular science
B. historical events
C. successful people
D. political systems

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科目: 来源:上海高考真题 题型:填空题

Directions: Complete the following passage by using the words in the box. Each word can only be
used once. Note that there is one word more than you need.
         A. launched        B. unpleasant        C. applying        D. technically        E. impact     
         F. coating        G. fixed        H. miraculously        I. superior        J. advances
     How would you like to wear the same underwear (内衣裤) for weeks? Owing to the work that
has gone into developing intelligent materials, this may not be as 1_____ as it sounds. Self-cleaning
clothes have now been created, and these new materials provide 2_____ resistance to dirt as well
as water. As a result, they require much less cleaning than traditional materials.
     The creation of self-cleaning clothes provides an example of how nature helps scientists develop
better products. This self-cleaning nature is known as the "lotus effect". The name comes, of course,
from the lotus leaves, which are famous for growing in muddy lakes and rivers while remaining almost
3_____ clean. By observing nature, scientists are 4_____ the qualities of the lotus leaves to the materials
they have engineered. Because of this, some remarkable new products have been 5_____. Among them
are special windows that are resistant to dirt and water. A special 6_____ on these windows not only
prevents dirt from sticking to their surfaces, but also allows dust to be easily washed off by the rain. In
fact, these new windows have already been 7_____ to some cars. Even when traveling at high speed
through rain, these cars never have to use their windshield wipers (雨刮器).
     Although we have already seen some practical applications, even more dramatic 8_____ will be made
in the future, and they will, perhaps, change our world completely. Undoubtedly, technology is an important
development, and it will have an even bigger 9_____ on our lives.

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