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.
B. become unhappy and inactive
C. are ready to leam their lessons
D. are active in doing school work
B. they are better at playing sports
C. they have enough energy to use
D. their personalities are more outgoing
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.
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.
B. A Recent Study on Health Problem
C. A Danger to Children"s Health
D. Sleep Time and Overweight
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. "
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
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
B. the idea of living beyond the present life span
C. the idea of living from 200 to 300 years
D. the conservative estimate
B. Science , Technology and Long Living
C. No Limit for Human Life
D. Healthy Lifestyle and Long Living
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.
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
B. Humans have begun destroying rainforests.
C. People have a strong desire for resources.
D. Much carbon dioxide comes from buming 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
B. How to Protect Nature
C. Rainforests and the Environment
D. Rainforests and Medical Development
Gadgets (小装置) can be wildly expensive and quickly out-of-date, but Steven Poole is still the
first to buy them. Technological innovations (创新) are often quite stupid. The idea that you might
want to walk down the street holding a mobile phone in front of your face, just to experience the
wonders of video calling, is clearly ridiculous. Luckily for the tech companies, however, there are
some people who jump at the chance to buy into new gadgets before they are fully ready and cheap
enough for the mass-market. They are called early adopters, and their fate is a terrible one. I should
know, since I am one myself.
Early adopters have a Mecca: it’s Tokyo’s Akihabara district, also known as “Electric City”.
There, in 1999, I bought a digital camera, a gizmo that few people in Britain had heard of. Over the
next few years I watched in great sadness as digital cameras became more popular, cheaper and more
powerful, until better models could be had for a quarter of the price I had paid. Did I feel stupid? What
I actually did was this: I splashed out more money last year for a new one, one that let me feel pleasantly
ahead of the curve once again. But I know that cannot last, and I’ll probably have to buy another in a
few years.
Thus early adopters are betting on other people eventually feeling the same desires. And it’s worse
if that future never arrives. Early adopters of the Betamax home-video format in the 1970s could only
look on in sadness when their investment was nullified（使无效）by the success of VHS. All sorts of
apparently splendid inventions, such as videogame consoles like the Atari Jaguar have been abandoned
to the dustbin of history right after a few early adopters bought in. Those who invested thousands in a
Segway motorized scooter on the wave of ridiculous advertising campaigns that accompanied its launch
a couple of years ago can join the club.
You might think we should just stop being so silly, save our money, and wait to see what really
catches on. But the logic of the industry is such that, if everyone did that, no innovation would become
popular. Imagine the third person to buy an ordinary telephone soon after Alexander Graham Bell had
invented it. Who was he going to call? Maybe he simply bought two phones, one for a special friend.
But still, the usefulness and eventual popularity of the device wasn’t clear at the time. Nobody dreamed
of the possibility of being able to speak to any one of millions of people. And yet if he, and the hundreds
and thousands of early adopters after him, had not bought into the idea, the vast communication networks
that we all take for granted today would never have been built.
The same goes, indeed, for all new technologies. Those guys holding bricks to their ears that we
laughed at in the 1980s made the current mobile phone possible. People who bought DVD players
when they still cost a fortune, instead of today’s cheap one at the local supermarket, made sure that
the new format succeeded. Early adopters’ desire for desires supported the future financially. And
what did they get for their pains? They got a hole in their bank accounts and inferior, unperfected
technology. But still, they got it first. And today they are still at work, buying overpriced digital radios,
DVD recorders and LCD televisions, and even 3G phones, so that you will be eventually be able to
buy better and less expensive ones.
So next time you see a gadget-festooned geek (满身新潮玩意的土包子) and feel tempted to
sneer (讥笑), think for a minute. Without early adopters, there would be no cheap mobile phones or
DVD players; there would be no telephone or television either. We are the tragic, unsung foot soldiers
of the technology revolution. We’re the desire-addicted pioneers, pure in heart, dreaming of a better
future. We make expensive mistakes so you don’t have to. Really, we are heroes.
B. present the main idea of the passage
C. prove the content of the passage is true
D. explain why modern technology is stupid
B. early adopters are probably welcomed by the tech companies
C. Mecca (para. 2) is a place where new digital cameras are designed
D. all the early adopters are very rich and enjoying buying anything new
B. What he buys proves useless and expensive.
C. He finds himself no longer the most fashionable.
D. What he buys doesn’t eventually become popular.
B. Because he had to buy another new camera in several years anyway.
C. Because the old camera made him feel upset and out of fashion.
D. Because early digital cameras were of poor quality and couldn’t last long.
B. Doubtful.
C. Critical.
D. Ashamed.
B. early adopters bravely spend much money buying new technology
C. early adopters are as a matter of fact clever investors of technology
D. early adopters help promote the development of technology
they don"t want to attend. lf a child seems upset or anxious about school, pretends to be sick to stay
home, repeatedly winds up in the nurse"s or principal"s office, or refuses to talk about the school day,
you should be concerned.
One fear that keeps children from enjoying school is separation anxiety. It most frequently occurs
during times of family problems or when a child is about to enter a new school. With younger kids, watch
how you say good-bye those first few days of school. A firm "Have a great day, and I"ll pick you up at
2: 30!" is more confidence-inspiring than" Don"t worry. I can be there in ten minutes if you need me. "
You can help your child handle fearful situations-from speaking up in class to taking tests-by
rehearsing at home. Help make large projects less discouraging by breaking them into manageable
pieces. Teach your child to replace thoughts such as "I"m going to fail" with" I can handle this".
Some kids dislike school because they have no friends. This may be the case if your child is always
alone, fakes illness to avoid class outings or gives away treasured possessions in an attempt to be liked.
Often loneliness problems can be solved by improving social skills. A child may need to learn how yo
look others in the eye when he speaks, or how to talk above a whisper -or below a yell. You might
teach a young child a few "friendship openers", such as "Myname"s Tom. What"s yours? Do you want to
play games?"
B. uncertain if he can deal with his family
C. eager to go to school
D. unwilling to leave his family for school
B. Taking an examination.
C. Finishing a lot of housework.
D. Doing a big amount of homework.
B. complaints about school
C. a loneliness problem
D. a fearful situation
( l)-Paragraph 1
(2)-Paragraph 2
(3)-Paragraph 3
(4)-Paragraph 4
B. (1)(2)→(3)(4)
↗ (2) ↗ (1)
C. (1)→(3)
D. (2)→(4)
↘ (4) ↘(3)
night"s sleep. Researchers from the University of Chicago asked volunteers to remember simple words.
Many found their memories letting them down towards the end of the day, but the following morning,
those who had slept well could recall much more. Reserchers , writing in the journal Nature .said the
brain coud " rescue"lost memories during the night.When the brain is first asked to remember something
that memory is laid down in an " unstable " state, meaning that it is possible that it could be lost. At
some point, the brain consolidates those it deems important into a "stable" , more permanent state.
However, the Chicago researchers suggested that it was possible for a " stable" memory to be made "
unstable" agan.This would mean that memories could be modified then filed away again in the face of
new experiences.
The 12 volunteers tested in the experiment were played words created through a speech synthesizer
which were purposely difficult to understand. Initially, the written version of the word was available,but
after wards the volunteers were asked to identify the word from the audio version only. Tests revealed
that the ability to recall the right word tended to tail off as the day ended.
However,when the volunteers were retested after a good night"s sleep,they were able to recall some
words that they had"forgotten" the previous evening. Dr Daniel, one of the study authors, said : " Sleep
consolidates memories , protecting them against subsequent interference or decay. Sleep also appears
to "recover" or restore memories. " He said : " If performance is reduced by decay , sleep might actively
recover what has been lost. "
Dr Karim Nader, from the Department of Psychology in McGill University in Montreal, said: " Memory
research is undergoing a transformation-no longer is memory thought to be a hard-wiring of" the brain ,
instead it seems to be a process of storage and restorage. "
Sleep helps some memories " mature" and also prunes out unimportant memories..
A. A busy day makes people forget things easily.
B. People need a good night"s sleep after a busy day.
C. A good night"s sleep helps memories.
D. A good night"s sleep helps people forget a busy day.
B. hard to understand
C. available at the beginning
D. designed to test people"s ability of understanding
B. is not a process of storage
C. is not a process of restorage
D. will be mature with the help of sleep
B. The brain will change those important unstable memories into stable.
C. Once the memory become stable, it will never become unstable again.
D. Sleep can protect memories from being harmed
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