brain lives for only three to five minutes. More often the doctors can"t fix the damage. Sometimes
they are afraid to try something to help because it is dangerous to work on the brain. The doctors
might make the person worse if he operates on the brain.
Dr. Robert White, a famous professor and doctor, thinks he knows a way to help. He thinks
doctors should make the brain very cold. If it is very cold, the brain can live without blood for
30 minutes. This gives the doctor a longer time to do something for the brain.
Dr. White tried his idea on 13 monkeys. First he taught them to do different jobs, then he
operated on them. He made the monkeys" blood go through a machine. The machine cooled
the blood. Then the machine sent the blood back to the monkeys" brains. When the brain"s
temperature was 10°C, Dr. White stopped the blood to the brain. After 30 minutes he turned
the blood back on. He warmed the blood again. After their operations the monkeys were like
they had been before. They were healthy and busy. Each one could still do the jobs the doctor
had taught them.
B. the patients are often too nervous
C. the damage is extremely hard to fix
D. the blood-cooling machine might break down
B. trying the operation on monkeys first
C. having the blood go through a machine
D. lowering the brain"s temperature
B. can keep the brain"s blood warm
C. can keep the patient"s brain healthy
D. can help monkeys do different jobs
a. send the cooled blood back to the brain
b. stop the blood to the brain
c. have the blood cooled down
d. operate on the brain
B. c, a, b, d
C. c, b, d, a
D. b, c, d,
benefits of water, could reduce their risk of getting extra pounds, reports a new study that
is published in the latest issue of the journal Pediatrics.
The findings are based on a survey in 32 elementary schools of two German cities, Dortmund
and Essen. The researchers, led by Rebecca Muckelbauer, a nutritionist(营养学家) at the
Research Institute of Child Nutrition Dortmund, weighed about 3,000 children, and asked
them about their beverage consumption(饮料消费量).
At the beginning of the school year, the experts had water fountains added to 17 of the schools.
The scientists also worked with teachers to carry out educational programs that promote the
benefits of drinking water. In contrast to schools in the United States, there are very few
schools in Germany that have water fountains.
At the beginning of the study, there were no big differences in the number of overweight children
in the different groups. But by the end of the school year, children in the schools with water
fountains were 31 per cent less likely to gain extra pounds, compared to kids who went to other
schools, where water drinking was not encouraged.
Children in the schools with fountains increased their water consumption from about 3 up to 4
glasses a day, while those in the other schools continued to drink an average of 3 glasses. Over
the research, the number of overweight kids upped from 384 to 385 out of 1,641 at the schools
with water fountains. In comparison, the number of overweight kids at the other schools increased
from 339 to 364 out of 1,309, Dr. Muckelbauer said.
The experts cannot make any final conclusions and explain why the students who were encouraged
to drink water were less likely to gain extra weight. Dr. Muckelbauer noted that according to a few
other studies, drinking of water increases the rate at which calories are burned, while some other
research suggested that water may temporarily decrease appetite (食欲).
B. mainly deals with the water drinking problem
C. is mainly about the mental health of kids
D. must be a journal entitled by a school
B. The students surveyed were all overweight.
C. It surveyed children in the countryside.
D. It lasted for a whole school year.
B. Further research is needed to support the finding.
C. The experts will encourage all the students to drink water.
D. Why students drinking more get less pounds will be clear soon.
B. Drink more water and become thinner
C. Water fountains at schools help kids stay thin
D. Water consumption at some German schools
1970 was World Conservation(自然保护)Year. The United Nations wanted everyone to know
that the world is in danger. They hoped that people would act quickly in order to conserve nature(大
自然). Here is one example of the problem. At one time there were 1,300 different plants, trees
and flowers in Holland, but now only 866 remain. The others have been destroyed by modern man.
It is said that there are tens of thousands of kinds of animals in the world, but now many have died
out(绝种). We are changing the earth, the air and water, and everything that grows and lives. We
can"t live without these things. If we continue like this, we shall destroy ourselves.
What will happen in the future?Perhaps it is more important to ask"What must we do now?"The
people who will be living in the world of tomorrow are the young of today. A lot of them know that
conservation is necessary. Many are helping to save our world. They plant trees, build bridges across
rivers and so on. In a small town in the United States a large group of girls cleaned the banks of 11
kilometres of their river. Young people may hear about conservation through a record called"No
one"s going to change our world."It was made by the Beatles, Cliff Richard and other singers. The
money from it will help to conserve wild animals.
B. an idea that nobody would accept(接受)
C. a record calling on people to conserve nature
D. a newspaper report in 1970
B. We should plant more trees and flowers.
C. We should clean the banks of our rivers.
D. We must do what we must do to save our world.
B. The United Nations wanted everyone to know that the world is in danger.
C. Conservation is necessary.
D. Young people are helping to save our world.
so it needs proper treatment and proper nourishment (营养).The old saying "An apple a day keeps
the doctor away "is not as silly as some people think. The body needs fruit and vegetables because
they contain vitamin C. Many people take extra vitamins in pill form, believing that these will make
them healthy.
But a good diet is made up of nourishing food and this gives all the vitamins you need. The body
doesn"t need or use extra vitamins, so why waste money on them?
In the modern western world, many people are too busy to bother about eating properly. They
throw anything into their stomachs, eating hurriedly and carelessly. The list of illnesses caused or
made worse by bad eating habits is frightening,
B. your body is made up of the food you eat
C. what you eat has great effect on your health
D. the more you eat, the fitter you will feel
B. the apple is the best among all kinds of fruits
C. apples can take the place of doctors
D. an apple is a sure cure for illness
B. often eating apples is a good habit
C. taking extra vitamin pills is completely useless
D. a good diet is of great importance for our health
B. lots of people"s illnesses are caused or made worse by bad eating habits
C. people throw everything into their stomachs without chewing
D. people are only too busy to cook meals for themselves
Most people know this joke. But recently, some people have been much more worried about how
the grizzly(灰白的) bear and mountain lion can cross the road.
"Millions of animals die each year on U.S. roads," the Federal Highway Administration reports. In
fact , only about 80 ocelots(豹猫), an endangered wild cat, exist in the U. S. today. The main reason?
Road kill.
"Eco-passages" may help animals cross the road without being hit by cars. They are paths both over
and under roads. "These eco-passages can be extremely useful, so that wildlife can avoid road accidents," said Jodi Hilty of the Wildlife Protection Society.
But do animals actually use the eco-passages? The answer is yes. Paul Beier of Northern Arizona
University found foot marks left by mountain lions on an eco-passage that went under a highway. This
showed that the lions used the passage.
Builders of eco-passages try to make them look like a natural part of an area by planting trees on and
around them. Animals seem to be catching on. Animals as different as salamanders(火蜥蜴)and
grizzly bears are using the bridges and underpasses(地下通道,下穿交叉道).
The next time you visit a park or drive through an area with a lot of wildlife, look around. You might
see an animal overpass(越过,通过)!
![](http://img.shitiku.com.cn/uploads/allimg/20191221/20191221083639-12040.png)
B. the driving conditions have improved greatly
C. the
![](http://img.shitiku.com.cn/uploads/allimg/20191221/20191221083639-71785.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191221/20191221083640-86334.png)
D. wild animals have become more dangerous
B. a fence(栅栏) built for the safety of the area
C. a passage(通道) for animals to cross the road
D. a bridge for animals to get over a river
B. animals begin to learn to use eco-passages
C. animals are crossing the road in groups
D. animals are becoming safer
B. call on drivers to be careful when seeing animals on roads
C. introduce a new way to help protect animals
D. tell us the main reason for the killing of animals in the US
environment. Often, this waste produced by major industries and people is harmful to both nature
and human life.
One of the main causes of the large amount of dangerous waste is that people do not realize
how large a problem it is. Because it can be simply removed and sent to a landfill(废渣填埋场),
the problem is often believed to end there. In addition, industries have often shown an unwillingness
to find ways to deal with dangerous waste because of the related expenses. Many industries and
governments build simple landfills to store waste, and often just pour waste chemicals into nearby
bodies of water. Often, chemicals used for industrial production cause dangerous forms of waste.
The amount of these chemicals has increased greatly in the past, but it is often difficult and expensive
to get rid of these chemicals or to store them in a way safe to human life and the environment.
Every year, major health problems result from dangerous waste. Sadly, it is often only after
someone has died or become seriously ill that governments will take measures to reduce levels of
harmful waste.
Some governments have realized how serious the dangerous waste problem is and are now trying
to settle this problem. They are also trying to limit the amount of waste industries are allowed to
produce.
Not only governments but ordinary people as well must work together to solve the problem.
They can choose not to buy those products which require the production of dangerous waste, and
produce less harmful waste themselves. Many scientists think that waste production can be cut. The
waste can be reduced by at least one third using existing technologies and methods.
B. Danger of Harmful Waste to Mankind
C. Dangerous Waste and Water Pollution
D. Environmental Protection
B. do not know where to place the dangerous waste
C. are not clear about how serious the dangerous waste problem is
D. are not sure about where harmful waste ends
B. How to increase their production.
C. How to store harmful waste.
D. How to cut down the related costs.
B. Present technologies have settled the harmful waste products.
C. Everyone should obey the government rules for the problem.
D. To solve the problem requires the efforts of the whole society.
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