American scientists答案解析

Special trees that grow faster, fight pollution, produce better wood, and even sense chemical attacks are being planted by scientists in the US．

         When 40 per cent of Hawaii's US$14 million-a-year papaya （木瓜）industry was destroyed by a virus five years ago, work began on creating genetically engineered（转基因的）trees．

         Researchers successfully introduced seeds that were designed to resist the virus．Since then, more and more people have been testing genetically engineered trees．Some researchers put special bacteria into trees to help them grow faster and produce better wood．Others are trying to create trees that can clean polluted soil．Meanwhile fruit farmers are looking for trees that are strong enough to resist worms, and paper companies want trees that produce more wood and therefore more paper．

         The Pentagon （五角大楼） even gave the researchers US$500,000 this year after they developed a pine tree that changes its colours if it senses a chemical attack．So far, the poplar, eucalyptus （杨树与桉树）, apple and coffee trees are among those being engineered．All this can be done today because we have a better understanding of tree genomes （基因组）．

         However, some people fear that the genetically engineered trees will cause dangerous results．They are worried that the new trees will breed with natural species and change the balance of the forest environment．

         “It could be destructive,” said Jim Diamond, an environmentalist. “Trees are what is left of our natural environment and home to many endangered species.”

         But researchers insist that science could give nature a fighting chance against both natural and man-made dangers．They hope to answer the critics by stopping the new trees from breeding, so their effect on the environment can be controlled．

63．Which kind of tree is not the ones that scientists are planting in the US?

         A．Trees that worms can't hurt．

         B．Genetically engineered trees．

         C．Trees that can resist wind better．

         D．Trees that can protect themselves at a chemical attack．

64．What caused the American scientists to work on special trees?

         A．Tree genomes are mapped out so scientists know how to improve trees．

         B．Great numbers of trees have been lost due to attacks by viruses．

         C．Researchers successfully introduced seeds designed to resist the virus．

         D．They think science could give nature a fighting chance against both natural and man-made dangers．

65．Which of the following was probably the first kind of trees being engineered?

         A．Papaya．                     B．Pine．                           C．Apple．                        D．Poplar．

66．Why did critics think engineered trees dangerous? Because ________．

         A．these trees can destroy the balance of nature

         B．everything except trees has been genetically engineered

         C．trees are home to many endangered species

         D．these trees may affect normal trees

A new report says sea ice in the Arctic Ocean is melting more quickly than expected. American scientists say the ice is melting even faster than computer programs had estimated.
Scientists know that climate change has a major effect on the Arctic Ocean partly because sea ice is disappearing. They also know that areas of open seawater are expanding. Such areas are known to take in sunlight and increase temperatures. Scientists say this has helped to cause the loss of the Arctic’s ice cover.
For the study, the American scientists compared eighteen computer programs with observations made by satellites and other instruments. The Intergovernmental Panel on Climate Change used the computer programs to prepare its 2007 estimates of climate change.
The computer programs gave estimates of the amount of ice in the Arctic Ocean in the month of September. September is when the Arctic has the least ice, after the warm, summer months. The computer estimates suggested an ice loss of two and a half percent for every ten-year period between 1953 and 2006.  
Newer studies of the Arctic have used information gathered by aircraft, satellites and ships. This information showed a loss of September ice cover of almost eight percent for every ten-year period between 1953 and last year. This means the ice is disappearing about thirty years faster than the computer programs estimated.
The scientists say the programs might not have recognized the full effect of increased carbon dioxide and other gases in Earth’s atmosphere. They say their study suggests the gases may have more of an effect than had been thought.
【小题1】It is reported that sea ice in the Arctic Ocean is melting more quickly than expected mainly because _________.

Honeybees are disappearing for unknown reasons around the United States．Last winter, bees disappeared from 23 percent of American beekeeping businesses．Causes of the phenomenon, however, have remained a mystery．

       Now, scientists from several universities and the United States Department of Agriculture say they have a possible explanation for the bee decline（数量下降）．It is a little known virus called Israeli acute--paralysis virus （IAPV） ．The virus kills bees．Researchers in Israel first described it in 2004 , but until now, bee experts hadn’t paid much attention to it．

       When trying to find out why the bees were disappearing, a research team at Columbia University studied bee colonies （ 群体）, some with and the others without decline．The research turned up large numbers of two types of fungi （真菌） once suspected of causing the bee decline．The research results, however, showed that the fungi were almost as common in colonies without a decline as they were in colonies with a decline．The researchers concluded that the two fungi probably weren’t the cause．

       Studies of the presence of IAPV, however, showed more interesting information．In those studies, done by a team at Pennsylvania State University in University Park, the virus showed up in 83 percent of samples from colonies with symptoms （症状）．Only five percent of samples from symptomless colonies had it．

       Scientists still don’t know whether IAPIV can single--handedly cause the bee decline．They believe that even if the virus is making colonies sick , it could have a partner in crime．It’s possible, for instance, that insects or chemicals in the environment weaken bees, making them more likely to catch IAPV．

       Scientists are still trying to figure out how IAPV came to the United States．The United States currently allows bee products to be imported from Canada, Australia, and New Zealand．If it turns out that this trade is spreading disease, the rules might eventually change．

1.According to the passage ，IAPV is a virus that ______．

       A．hasn’t attracted much attention

       B．well-known to doctors and scientist

       C．was first found by Austrian researchers

       D．is dangerous to animals and human beings

2.The underlined sentence in the fifth paragraph probably means______．

       A．the virus could also cause other damages

       B．there must be something that is the real cause

       C．IAPV is not the only cause for the bee decline

       D．the virus may be caused by the polluted environment

3.From the third and fourth paragraphs, we know researchers draw their conclusions by means of _______．

       A．calculating      B．comparing      C．examining           D．investigating

4.What still remains unknown to American scientists according to the passage?

       A．How and why to kill IAPV．

       B．How IAPV came to America．

       C．Whether bee products should be imported．

       D．How to change the rules of the bee products trade．

5.The best title for this passage would be _____．

       A．Bee Disease         B．How to Kill IAPV

       C．A Virus—IAPV     D．Two Types of Fungi

任务型阅读 (共10小题；每小题1分，满分10分)

注意：每个空格只填1个单词

The health dangers of smoking have been well reported. For years, doctors have warned that smoking can cause lung cancer. Studies also have linked smoking to several other kinds of cancer, heart attacks and other diseases, lung diseases, and a number of other medical problems. The repeated health warnings have had an effect. Thousands of people have stopped smoking. But as many people have learned, stopping smoking can be very difficult.

A major problem apparently is the nicotine, a poisonous substance found in tobacco. Small amounts of nicotine are released as tobacco is burned. And over many years of smoking, a person’s body becomes dependenton the substance. A try to stop smoking brings the problems of nicotine withdrawal（脱瘾过程）.

American medical researchers have found that nicotine withdrawal causes people to become angry very easily, aggressive, worried and unable to think sharply. Many people who have tried to stop smoking would confirm those findings.

To help people give up smoking, some tobacco companies have proposed chewing tobacco, or using snuff as safe substitutes（替代物）. Snuff is a tobacco powder that usually is breathed in. But many people put it between their gum and cheek.

A group of British scientists said recently that many lives could be saved by a major program to get cigarette smokers to change to snuff. An American scientist, Allan Blum, disagreed. Dr. Blum argued that snuff, put in the mouth, can cause gum disease, teeth problems and throat problems that lead to cancer. Dr. Blum also warned against chewing tobacco as a substitute for smoking. He said chewing tobacco can lead to cancer of the mouth, throat or digestive system.

Medical researchers say another possible substitute for smoking is a special nicotine chewing gum. The gum is already sold in Europe and Canada. A report says research shows that the chewing gum will increase the amount of nicotine in a person’s blood. This helps satisfy some people’s desire for a cigarette. However, the report says, the chewing gum also leads to some unpleasant side effects. And it may be dangerous for people with heart problems.

Two other American scientists say they have found that the most effective way to stop smoking is to do it completely, suddenly, all at once. The report by Saul Shirtman and Dr. Murray Jogbett says that by stopping all at once, the worst problems of nicotine withdrawal are over in just a few days. But, they say, by continuing to smoke, even a little less each day, the problems of withdrawal never end completely.

     One woman in nine will develop breast cancer (乳腺癌) over her lifetime. However, a healthy diet can reduce your risk of developing the disease by 40 to 60 percent.

     Generally speaking, eating more vegetables can reduce your risk of developing breast cancer by 60 percent. Vegetables like cabbage are rich in fiber (纤维), can lower your risk of developing breast cancer. To get the most from their goodness, it's recommended that you eat at least three to four cups of these vegetables per week.

     It's the oleic acid (油酸) contained in olive oil. American scientists conducting laboratory research have observed that oleic acid has a beneficial effect on breast cancer cells. Olive oil is the richest source of this acid, so whenever possible, use it in place of butter.

     Eating fruit is another excellent way to help prevent the development of breast cancer. In fact, women who do eat fruit are six percent less likely to develop the disease. The American Institute for Cancer Research considers berries (浆果类) (blueberries, strawberries, etc.) to be powerful for breast cancer fighters.

     It's the lycopene (番茄红素), found in great quantities in tomatoes, that can reduce the risk of developing breast cancer. The lycopene found in canned tomatoes is more readily absorbed by the body than that contained in fresh ones, so add tomato juice, paste, and sauce to your diet.

     As a result of various studies, the American Institute for Cancer Research has concluded that components (成分) found in green tea can help halt the development of cancerous tumours (瘤) and even prevent them from appearing in the first place. Three cups a day will help you get the benefits of green tea.

What does the author mainly tell us?

How to cure breast cancer by eating healthy foods.

Healthy diets help fight against breast cancer.

Proper fruits, vegetables and drinks keep you fit.

Breast cancer is the most terrible killer for women.

We learn from the passage that ________.

eating more fruit and vegetables can stop your risk of developing cancer

olive oil can help breast cancer cells develop

women eating tomatoes won't suffer from breast cancer

components found in green tea can reduce the risk of developing cancer

What does the underlined word "halt"in the last paragraph mean?

According to the passage, the author may agree that ________.

A. Ten percent of women suffer from breast cancer

B. Berries are the richest source of the oleic acid

C. The lycopene found in olive oil has a good effect on breast cancer cells

D. Drinking green tea properly can help you keep healthy

Recently some American scientists have given a useful sincere piece of advice to people in industrialized nations that they would be much healthier if they ate more of the same kind of food eaten by humans living more than 10,000 years ago.

The scientists say that the human body has changed very little since humans first appeared on the earth, but the way we live has changed greatly. Our body has not been able to deal with these changes in life style and this has led to new kinds of sicknesses. These new sicknesses were not known in ancient times, so they are called “diseases of civilization”. Many cancers and diseases of the blood system, including heart attacks and strokes ( 中风 ) are examples of such diseases.

Scientists noted that people in both the Old Stone Age and the New Stone Age enjoyed very little alcohol or tobacco, probably none. Ancient people also got a great deal of physical exercise, but a change in food is one of the main differences between life in ancient times and that of today.

Stone-age people hunted wild animals for their meat, which had much less fat than domestic or tame ones ( 家畜 ). They also ate a lot of fresh wild vegetables and fruits. They didn’t have milk or any other dairy products, and they made very little use of grains. But today, we eat a large amount of these. We eat six times more salt than our remote ancestors. We eat more sugar. We eat twice as much fat but only one third as much protein and much less vitamin C.

People today probably do not want to live the way people thousands of years ago did, but scientists say that we would be much healthier if we ate much the same way as remote ancestors did, cutting the amount of fatty, salty and sweet food.

What is the main cause that people suffer from a lot of new sicknesses?

A. Ancient people did a great deal of physical exercise.

B. People today have a lot of alcohol.

C. People today have more tobacco.

D. Food today is quite different from that of ancient times.

Which of the following belongs to the dairy products?

A. Milk              B. Corn     C. Pork             D. Flour

New kinds of sicknesses have been found because ________.

A. the human body has changed compared with humans who first appeared on the earth

B. the way we live has changed a little

C. our body can’t deal with the changes in life style

D. the way we live today is proper for the human body

According to some scientists, Stone-age people were much healthier than people today because they ate a lot of ________.

A. milk and other dairy products                        B. salt and sugar

C. wild animals, fresh wild vegetables and fruits     D. grain foods

British and American scientists are raising genetically modified(转基因的) pigs in the hope of providing organs for transplant(移植) to humans, the project leader wrote in a newspaper Sunday.
Scientists in London and California have begun conducting the genetic experiments to find a solution to record–long waiting lists for organ transplants, Robert Winston said in an opinion piece written for Britain's Sunday Times.
In Britain alone, around 8,000 patients are waiting for a transplant.
"People needing a new heart or liver are waiting for someone else to die – usually a violent death in a traffic accident," Winston wrote in the newspaper. He said his team was "trying to modify pigs so their organs might save the lives of humans."
The scientists are introducing human genes into the animals to reduce the chances of the organs being rejected by patients, as has been common in previous attempts to use animal tissues, said Winston, who heads the Institute of Reproductive and Developmental Biology at London's Hammersmith Hospital.
Working with Dr. Carol Redhead of the California Institute of Technology, Winston's team has injected human genes directly into male piglets(猪仔), adding them to the animal's sperm(精子).
He said that pigs involved in experiments had successfully produced transgenic sperm, but acknowledged that British and European laws had prevented the team from using the pigs to mate.
The Sunday Times newspaper reported that the experiments would be moved to the United States following difficulties with funding and regulations in Britain. It said the pigs would be bred in Missouri.
"Our U.S. friends will benefit from our technology and the income we might have produced for Britain will be lost," Winston wrote.
Some scientists have previously blamed the idea of using animal organs for human transplant, saying the technique risks spreading animal viruses to humans. Winston said his research project is attempting to breed virus-free pigs.
49. Scientists are introducing human genes into the animals to ____________.

A new report says sea ice in the Arctic Ocean is melting more quickly than expected. American scientists say the ice is melting even faster than computer programs had estimated.

Scientists know that climate change has a major effect on the Arctic Ocean partly because sea ice is disappearing. They also know that areas of open seawater are expanding. Such areas are known to take in sunlight and increase temperatures. Scientists say this has helped to cause the loss of the Arctic’s ice cover.

For the study, the American scientists compared eighteen computer programs with observations made by satellites and other instruments. The Intergovernmental Panel on Climate Change used the computer programs to prepare its 2007 estimates of climate change.

The computer programs gave estimates of the amount of ice in the Arctic Ocean in the month of September. September is when the Arctic has the least ice, after the warm, summer months. The computer estimates suggested an ice loss of two and a half percent for every ten-year period between 1953 and 2006.  

Newer studies of the Arctic have used information gathered by aircraft, satellites and ships. This information showed a loss of September ice cover of almost eight percent for every ten-year period between 1953 and last year. This means the ice is disappearing about thirty years faster than the computer programs estimated.

The scientists say the programs might not have recognized the full effect of increased carbon dioxide and other gases in Earth’s atmosphere. They say their study suggests the gases may have more of an effect than had been thought.

It is reported that sea ice in the Arctic Ocean is melting more quickly than expected mainly because _________.

A. climate change                        B. sea ice’s disappearance  

C. seawater’s expansion              D. the loss of the Arctic’s ice cover

How did the scientists draw the conclusion that sea ice in the Arctic Ocean is melting more quickly than expected?

A. The scientists have been observing the Arctic Ocean for many years.

B. The scientists have compared the computer programs with observation made by satellites and other instruments.

C. The scientists have figured out many numbers with the help of computer.

D. The scientists have found that the seawater take in sunlight and increase temperatures.

If the ice melts at the present speed, by the end of this century the ice loss in the Arctic Ocean will be _________ according to newer studies.

A. 22.5%                B. 35%          C.72%         D. 100%

Which of the following is TRUE according to the passage?

A. The figures of the computer estimates are wrong.

B. Scientists study climate change through studying sea level.

C. Newer studies show gases may have more effect on sea ice in the Arctic Ocean.

D. The ice is melting even faster than satellites have estimated.

This report mainly warns human to _________.

A. prevent the sea ice in the Arctic Ocean from melting any more

B. pay more attention to the loss of the Arctic’s ice cover 

C. take necessary steps to protect the environment of our earth

D. stop summer sea ice in the Arctic from disappearing so fast

A new report says sea ice in the Arctic Ocean is melting more quickly than expected. American scientists say the ice is melting even faster than computer programs had estimated.

Scientists know that climate change has a major effect on the Arctic Ocean partly because sea ice is disappearing. They also know that areas of open seawater are expanding. Such areas are known to take in sunlight and increase temperatures. Scientists say this has helped to cause the loss of the Arctic’s ice cover.

For the study, the American scientists compared eighteen computer programs with observations made by satellites and other instruments. The Intergovernmental Panel on Climate Change used the computer programs to prepare its 2007 estimates of climate change.

The computer programs gave estimates of the amount of ice in the Arctic Ocean in the month of September. September is when the Arctic has the least ice, after the warm, summer months. The computer estimates suggested an ice loss of two and a half percent for every ten-year period between 1953 and 2006.  

Newer studies of the Arctic have used information gathered by aircraft, satellites and ships. This information showed a loss of September ice cover of almost eight percent for every ten-year period between 1953 and last year. This means the ice is disappearing about thirty years faster than the computer programs estimated.

The scientists say the programs might not have recognized the full effect of increased carbon dioxide and other gases in Earth’s atmosphere. They say their study suggests the gases may have more of an effect than had been thought.

1.It is reported that sea ice in the Arctic Ocean is melting more quickly than expected mainly because _________.

A. climate change                        B. sea ice’s disappearance  

C. seawater’s expansion              D. the loss of the Arctic’s ice cover

2. How did the scientists draw the conclusion that sea ice in the Arctic Ocean is melting more quickly than expected?

A. The scientists have been observing the Arctic Ocean for many years.

B. The scientists have compared the computer programs with observation made by satellites and other instruments.

C. The scientists have figured out many numbers with the help of computer.

D. The scientists have found that the seawater take in sunlight and increase temperatures.

3.If the ice melts at the present speed, by the end of this century the ice loss in the Arctic Ocean will be _________ according to newer studies.

A. 22.5%                B. 35%          C.72%         D. 100%

4.Which of the following is TRUE according to the passage?

A. The figures of the computer estimates are wrong.

B. Scientists study climate change through studying sea level.

C. Newer studies show gases may have more effect on sea ice in the Arctic Ocean.

D. The ice is melting even faster than satellites have estimated.

5.This report mainly warns human to _________.

A. prevent the sea ice in the Arctic Ocean from melting any more

B. pay more attention to the loss of the Arctic’s ice cover 

C. take necessary steps to protect the environment of our earth

D. stop summer sea ice in the Arctic from disappearing so fast

根据短文内容，从短文后的选项中选出能填入空白处的最佳选项。选项中有两项为多余选项。

Recently some American scientists have given a useful piece of advice to people in industrialized nations. They say people should eat more of the same kind of food eaten by humans living more than 10,000 years ago. ___1.___

The scientists say that the human life has changed greatly. Our bodies have not been able to deal with these changes in lifestyle and this had led to new kinds of sickness. ___2.___ So they are called “disease of civilization”. Many cancers and diseases of the blood system are examples of such diseases.

Scientists noticed that people in both the Old Stone Age and the New Stone Age enjoyed very little alcohol or tobacco, probably none. __3.___ However, a change in food is one of the main differences between life in ancient times and that of day.

Stone Age people hunted wild animals for their meat, which had much less fat than domestic ones. They ate a lot of fresh wild vegetables and fruits. They did not have milk or any other dairy product, and they made very little use of grains.

___4.___ We eat six times more salt than our ancestors(祖先). We eat more sugar. We eat twice as much fat but only one third as much protein and much less vitamin C.

___5.___ But scientists say that we would be much healthier if we eat much the same way as our ancestors did, cutting the amount of fatty, salty and sweet food.

A.  These new sicknesses were not known in ancient times.

B.  People today probably don’t want to live the way people thousands of years ago did.

C.  Ancient people also lived in large groups.

D.  But today, we eat a lot of these.

E.  Ancient people also got a great deal of physical exercise.

F.  In that case, they would live much healthier.

G. People today probably live the same life as people thousands of years ago did.

Cloud seeding is a method of artificially causing clouds to produce precipitation （降水） in the form of rain or snow．Cloud seeding has also been used in attempts to modify the severity of hail storms and hurricanes．The effectiveness of cloud seeding remains controversial （有争议的）．but it continues to be used in some regions to try to increase rainfall for agriculture and to build snow packs for water supplies and power production．

Cloud seeding was developed by American scientists Irving Langmuir and Vincent Joseph Schaefer during and after World War II．Their work began as an effort to learn more about the buildup of ice on airplane wings, and eventually led them to attempt to create rainfall by releasing several pounds of crushed frozen carbon dioxide into a cloud from an airplane．In this form, the carbon dioxide is called dry ice．On November 13, 1946, the technique appeared to produce snow directly under the cloud; the snow then turned to rain as it fell to the ground．

For their experiment, Langmuir and Schaefer selected a supercooled cloud, one in which the water droplets remain liquid in subfreezing temperatures．Their theory was that small grains of dry ice falling through the cloud would cause tiny droplets of water vapor in the cloud to freeze into crystals that attracted more water vapor．Their theory proved to be correct and eventually the crystals became heavy enough to fall from the cloud as snow．As the snow reached the warmer temperatures closer to the ground, it melted and became rain．

Another scientist, Bernard Vonnegut, produced a method of cloud seeding using silver iodide （碘化银）．He used particles of silver iodide because its crystal structure resembled that of ice in clouds．Silver

iodide also had practical advantages over frozen carbon dioxide It could be stored at room temperature

and did not require an airplane as a delivery mechanism．Instead, silver iodide crystals could be fired by

cannons （大炮） high into the air, where wind carried them into the clouds．

1.According to the text, Langmuir and Schaefer had intended to deal with__

A．how to freeze carbon dioxide                      

B．how to remove ice on plane wings

C．how to make weather forecast for the war             

D how to hide planes in clouds at war

2.What is the CORRECT order of the course for cloud seeding with dry ice?

a．snow becoming rain in wanner temperatures             b．crystals attracting more water vapor

c．crystals falling in the form of snow                     d．crystals becoming very heavy

e．freezing tiny droplets of water vapor into crystals

f．putting small grains of dry ice in the cloud

A．a-c-f-d-b-e                              B．b-f-e-a-c-d            

C．f-e-b-d-c-a                      D．e-a-d-c-b-f

3.Bernard chose silver iodide as a method of cloud seeding because___．

A．it is much cheaper than dry ice                     B．it can be stored at any rooms

C．it can be sent into clouds by wind                 D．it is similar

4.The best title for the passage may be "____"．

A．Cloud Seeding                    

B．Artificial Raining       

C．Weather Changing

D．Cloud Gathering

5.How many methods of cloud seeding are mentioned in the passage?

A．three               B．two                     C．one              D.four

US universities are among the best in the world. Since World War Ⅱ, American scientists --- mostly working in universties or colleges --- have won more than half of all Nobel Prizes in physics and medicine. Foreign students rush to the United States by the tens of thousands. Last year they earned more than one quarter of the doctoral degrees awarded in the country. Yet while American universities produce the great research and great graduate program, they sometimes pay little attention to the task that lies at their very core: the teaching of undergraduate students.

With the increase in fees, educators feel obliged to improve undergraduate teaching. In speeches and interviews the nation’s higher educators have rediscovered teaching. Robert Rosenzweig, president of the Association of American Universities,  said,  “Our organization was never very concerned about teaching. In the last 18 months, we have spent more time on undergraduate education than on any other subject.”

Despite such promising efforts, no one doubts that research still outranks teaching at some of the leading universities, not least because it is a surer and faster way to earn status. Some people don’t think it has to be that way. They argue that the reward system for college faculty can be changed, so that professors will be encouraged to devote more time and effort to teaching. They say that they are beginning to believe that the first ten years of the 21st century may come to be remembered as the decade of the undergraduate.

That would bring it full circle. For more than two centuries after the founding of Harvard College in 1636, the instruction of undergraduate students was an essential condition of American higher education.

1.According to the passage, at some of the leading American universities ________.

A．research is declining in importance          B．teaching now ranks above research

C．teaching is a sure way to gain position        D．research still ranks above teaching

2.It is implied in the passage that about 200 years ago undergraduate instruction ________.

A．began to change all of a sudden

B．was already threatened by research work

C．was the central part of higher education

D．began to be neglected in most universities

3.What would be the best title for the passage?

A．University education in the US             B．University education challenged

C．Teaching and research in universities        D．Undergraduate teaching rediscovered

Experts say that agriculture provides fourteen percent of the world's greenhouse gas emissions each year．The gases released include carbon dioxide, a major cause of global warming．
Twenty-one nations around the world recently joined forces to better understand and prevent greenhouse gas emissions from farms．The Global Research Alliance on Agricultural Greenhouse Gases was launched at the United Nations conference on climate change．The meeting took place in Copenhagen, Denmark last month．
Agricultural experts blame a number of farm activities for producing greenhouse gases．For example, animal waste and cattle digestive systems release methane （甲烷，沼气） gas．Fertilized soil and the burning of crop waste also release harmful gases into the air．Experts say some methods of farming ?turning the soil to prepare for planting ?also release harmful carbon dioxide．
An official of the European Commission's Directorate General for Research says agricultural greenhouse gas emissions can be cut．Maive Rute suggests feeding animals a diet designed to reduce emissions．
The new agricultural research group says protecting against global warming is only part of its purpose．It says the world also needs to develop better farming methods to feed growing populations in poor countries．
United States Agriculture Secretary Tom Vilsack said no one single nation can fight agricultural greenhouse gas emissions and increase food production at the same time．This is why the alliance is important for combining resources and finding new ones．
The United States Department of Agriculture will increase spending on farm emissions research by ninety million dollars over the next four years．The total will reach one hundred thirty million dollars．The U．S．D．A．will share the research with other countries in the Global Research Alliance on Agricultural Greenhouse Gases and support researchers from developing countries that belong to the alliance．Money from the Borlaug Fellowship program will let the researchers study agricultural climate change with American scientists．
Mister Vilsack said that just as climate change has no borders, there should be no borders for research．
72．In Paragraph 4, Maive Rute recommends _____．
A．increasing food production
B．changing cattle digestive systems
C．developing better fanning methods
D．giving animals the food meant to produce fewer emissions
73．The underlined word "alliance" in Paragraph 6 probably means _____．
A．Action or state being joined together
B．An agreement signed between countries
C．A program or project set up for a research
D．An organization formed for different goals
74．How much has the U．S．D．A．spent on farm emissions research so far?
A．130 million dollars．           B．220 million dollars．
C．40 million dollars．                D．90 million dollars．
75．The purpose of the passage is to ____．
A．suggest a total ban on farm activities
B．introduce Copenhagen conference held last month
C．appeal to more countries to cut agricultural emissions
D．inform readers of the major cause of global warming

Special trees that grow faster, fight pollution, produce better wood, and even sense chemical attacks are being planted by scientists in the US.

    When 40 per cent of Hawaii's US$14 million-a-year papaya (木瓜)industry was destroyed by a virus five years ago, work began on creating genetically engineered(转基因的) trees.

    Researchers successfully introduced seeds that were designed to resist the virus. Since then, more and more people have been testing genetically engineered trees.

    Some researchers put special bacteria into trees to help them grow faster and produce better wood. Others are trying to create trees that can clean polluted soil.

    Meanwhile fruit farmers are looking for trees that are strong enough to resist worms, and paper companies want trees that produce more wood and therefore more paper.

    The Pentagon (五角大楼) even gave the researchers US$500,000 this year after they developed a pine tree that changes its colours if it senses a chemical attack..

    So far, the poplar, eucalyptus (杨树与桉树), apple and coffee trees are among those being engineered. All this can be done today because we have a better understanding of tree genomes(基因组).

    However, some people fear that the genetically engineered trees will cause dangerous results. They are worried that the new trees will breed with natural species and change the balance of the forest environment.

"It could be destructive," said Jim Diamond, an environmentalist. "Trees are what is left of our natural environment and home to many endangered species."

    But researchers insist that science could give nature a fighting chance against both natural and man-made dangers.

    They hope to answer the critics by stopping the new trees from breeding, so their effect on the environment can be controlled.

What trees are NOT the ones that scientists are planting in the US?

A. Trees that worms can't hurt.   

B. Trees that can protect themselves at a chemical attack.

C. Trees that can resist wind better.    

D. Trees that can improve soil conditions.

What caused the American scientists to work on special trees?

A. They think science could give nature a fighting chance against both natural and man-made dangers.

B. Great numbers of trees have been lost due to attacks by viruses.

C. Researchers successfully introduced seeds designed to resist the virus.

D. Tree genomes are mapped out so scientists know how to improve trees.

Which of the following was probably the first kind of trees being engineered?

A. Papaya.                    B. Pine.                 C. Apple.               D. Poplar.

The best title of the passage is         .

A. The improvement of environment

B. The side-effects of special trees

C. The development of special trees

D. the program of genetically engineered trees

第三部分 阅读（共两节，满分40分）
阅读理解（共15小题，每小题2分，满分30分）      
阅读下列短文，从每题所给的四个选项（A、B、C和D）中，选出
最佳选项，并在答题卡上将该项涂黑。
Two American scientists told the people in industrial nations（工业国） that they would be much healthier if they ate more of the same kind of foods eaten by humans living more than 10,000 years ago．
The scientists say that the human body has changed very little since human first appeared on earth, but the way we live has changed greatly．Our body has not been able to deal with these changes in life style and this has led to new kinds of sicknesses．These new sicknesses were not known in ancient times．So they are called “diseases of civilization （文明）”．Many cancers and diseases of the blood system, including heart attacks （心脏病）and strokes（中风）are examples of such diseases．
Scientists noted that early stone-age people used very little alcohol（酒精） or tobacco, probably none．Ancient people also got a great deal of physical exercise, but a change in food is one of the main differences between life in ancient times and life today．
Stone-age people hunted wild animals for their meat, which had much less fat than farm animals．They also ate a lot of fresh wild vegetables, and fruits．They did not use milk and other dairy products, and they made very little use of grains．But today, we eat a large amount of dairy products and grain foods．We eat six times more salt than stone-age people．We eat more sugar．We eat twice as much fat but only one third as much protein（蛋白质）and much less vitamin C．
People today probably do not want to live as people thousands of years ago did, but scientists say that we would be much healthier if we ate as those ancient people did, cutting the amount of fatty, salty and sweet foods．
1．The people in industrial nations would be much healthier if they ate              ．
A．more foods as humans living 10,000 years ago did
B．as humans living 10,000 years ago
C．more kinds of food eaten by people living over 10,000 years ago
D．more of the same kinds of foods eaten by people over 10,000 years ago．
2．New kinds of sicknesses have been found because                       ．
A．the human body has changed compared with human first appeared on earth
B．the way we live has changed a little
C．our body can’t deal with the changes in life style
D．the way we live today is proper for the human body
3．What is the main cause mentioned in the article why people suffer from a lot of new sicknesses?
A．Ancient people did a great deal of physical exercise
B．People today have a lot of alcohol    
C．People today have more tobacco
D．Food is quite different between life today and life in ancient times
4．Stone-age people were much healthier than people today because they ate a lot of         ．
A．milk and other dairy products     
B．grain foods and farm animals
C．salt and sugar                       
D．wild animals, fresh wild vegetables and fruits
5．From this article, we know that                        are not good to our health．
A．protein and vitamin                            
B．milk and grain foods
C．wild animals, vegetables and fruits
D．a huge amount of fatty, salty and sweet foods

根据短文内容，从短文后的选项中选出能填入空白处的最佳选项。选项中有两项为多余选项。
Recently some American scientists have given a useful piece of advice to people in industrialized nations. They say people should eat more of the same kind of food eaten by humans living more than 10,000 years ago. ___【小题1】___
The scientists say that the human life has changed greatly. Our bodies have not been able to deal with these changes in lifestyle and this had led to new kinds of sickness. ___【小题2】___ So they are called “disease of civilization”. Many cancers and diseases of the blood system are examples of such diseases.
Scientists noticed that people in both the Old Stone Age and the New Stone Age enjoyed very little alcohol or tobacco, probably none. __【小题3】___ However, a change in food is one of the main differences between life in ancient times and that of day.
Stone Age people hunted wild animals for their meat, which had much less fat than domestic ones. They ate a lot of fresh wild vegetables and fruits. They did not have milk or any other dairy product, and they made very little use of grains.
___【小题4】___ We eat six times more salt than our ancestors(祖先). We eat more sugar. We eat twice as much fat but only one third as much protein and much less vitamin C.
___【小题5】___ But scientists say that we would be much healthier if we eat much the same way as our ancestors did, cutting the amount of fatty, salty and sweet food.

Honeybees are disappearing for unknown reasons around the United States．Last winter, bees disappeared from 23 percent of American beekeeping businesses．Causes of the phenomenon, however, have remained a mystery．

       Now, scientists from several universities and the United States Department of Agriculture say they have a possible explanation for the bee decline（数量下降）．It is a little known virus called Israeli acute--paralysis virus （IAPV） ．The virus kills bees．Researchers in Israel first described it in 2004 , but until now, bee experts hadn’t paid much attention to it．

       When trying to find out why the bees were disappearing, a research team at Columbia University studied bee colonies （ 群体）, some with and the others without decline．The research turned up large numbers of two types of fungi （真菌） once suspected of causing the bee decline．The research results, however, showed that the fungi were almost as common in colonies without a decline as they were in colonies with a decline．The researchers concluded that the two fungi probably weren’t the cause．

       Studies of the presence of IAPV, however, showed more interesting information．In those studies, done by a team at Pennsylvania State University in University Park, the virus showed up in 83 percent of samples from colonies with symptoms （症状）．Only five percent of samples from symptomless colonies had it．

       Scientists still don’t know whether IAPIV can single--handedly cause the bee decline．They believe that even if the virus is making colonies sick , it could have a partner in crime．It’s possible, for instance, that insects or chemicals in the environment weaken bees, making them more likely to catch IAPV．

       Scientists are still trying to figure out how IAPV came to the United States．The United States currently allows bee products to be imported from Canada, Australia, and New Zealand．If it turns out that this trade is spreading disease, the rules might eventually change．

According to the passage ，IAPV is a virus that ______．

       A．hasn’t attracted much attention

       B．well-known to doctors and scientist

       C．was first found by Austrian researchers

       D．is dangerous to animals and human beings

The underlined sentence in the fifth paragraph probably means______．

       A．the virus could also cause other damages

       B．there must be something that is the real cause

       C．IAPV is not the only cause for the bee decline

       D．the virus may be caused by the polluted environment

From the third and fourth paragraphs, we know researchers draw their conclusions by means of _______．

       A．calculating      B．comparing      C．examining           D．investigating

What still remains unknown to American scientists according to the passage?

       A．How and why to kill IAPV．

       B．How IAPV came to America．

       C．Whether bee products should be imported．

       D．How to change the rules of the bee products trade．

The best title for this passage would be _____．

       A．Bee Disease         B．How to Kill IAPV

       C．A Virus—IAPV     D．Two Types of Fungi

完形填空（共20小题；每小题1.5分，满分30分）

In the north of Scotland there is a lake called Loch Ness. It is the biggest   36   in Britain. It is over thirty kilometers 37 and in some places nearly 300 meters deep . It is cold and dark and not many people went there until after 1930. Then a road was made   38   the lake.

     Holiday makers began to use the road, and this was when the   39   began. Someone said that he had seen a monster(怪兽) in the lake. He said it was twelve meters long. It had a long   40  and a small head. Then someone else said he had seen  41  . Others said the same thing and in 1933 a London doctor took a  42  . It  43   like a monster with a long neck and a thick body but the photo was not too   44 . The newspapers printed the picture and   45   it the Loch Ness monster, or "Nessie".

     Then the argument(争论) began.   46 people, however, were certain there was something living in the lake. Others said there was   47  there.

     In 1961, a lot of people joined together to make a real  48   to see and photograph the monster to find   49  there was one! Several times people thought they saw something but after ten years there was  50   no real proof (证据).

     Later underwater television cameras were used, but   51   found any real proof. However, they   52  find something interesting: a huge underwater cave. It was big enough to be   53   of a monster, but of course, this was not a proof.

     In 1975, however, some American scientists  54  a search group. They used an underwater camera. It took pictures every seventy seconds. Some of the pictures seemed to show a red-brown creature. Its body was about four meters long  55   had a very ugly head on the end of a four -meter neck. Many people then began to believe in the monster. But even today we can't be certain.

A. river                  B. ocean                C. sea             D. lake

A. wide              B. tall               C. long               D. high

A. in                B. over                 C. around          D. above

A. accidents         B. meetings             C. sayings              D. stories

A. eye               B. ear               C. nose                D. neck

A. it                 B. one                  C. some                 D. all

A. photo               B. map             C. gun                  D. chance

A. sounded             B. looked            C. feel                D. would

A. clean             B. clear                C. taken            D. shown

A. called             B. believed             C. thought              D. regarded

A. Some                B. More                 C. All                  D. No

A. nothing           B. anything             C. monsters             D. everything

A. effort                 B. thing                C. interest             D. trip

A. so                 B. but                  C. as                   D. if

A. even              B. still                C. also            D. yet

A. someone            B. no one               C. anyone               D. we

A. did                B. really               C. were                 D. actually

A. room              B. house                C. home                 D. ground

A. found              B. formed(组成)       C. invited           D. get

A. but               B. or                C. and            D. however

Recently some American scientists have given a useful sincere piece of advice to people in industrialized nations that they would be much healthier if they ate more of the same kind of food eaten by humans living more than 10,000 years ago.

The scientists say that the human body has changed very little since humans first appeared on the earth, but the way we live has changed greatly. Our body has not been able to deal with these changes in life style and this has led to new kinds of sicknesses. These new sicknesses were not known in ancient times, so they are called “diseases of civilization”. Many cancers and diseases of the blood system, including heart attacks and strokes ( 中风 ) are examples of such diseases.

Scientists noted that people in both the Old Stone Age and the New Stone Age enjoyed very little alcohol or tobacco, probably none. Ancient people also got a great deal of physical exercise, but a change in food is one of the main differences between life in ancient times and that of today.

Stone-age people hunted wild animals for their meat, which had much less fat than domestic or tame ones ( 家畜 ). They also ate a lot of fresh wild vegetables and fruits. They didn’t have milk or any other dairy products, and they made very little use of grains. But today, we eat a large amount of these. We eat six times more salt than our remote ancestors. We eat more sugar. We eat twice as much fat but only one third as much protein and much less vitamin C.

People today probably do not want to live the way people thousands of years ago did, but scientists say that we would be much healthier if we ate much the same way as remote ancestors did, cutting the amount of fatty, salty and sweet food.

1.What is the main cause that people suffer from a lot of new sicknesses?

A. Ancient people did a great deal of physical exercise.

B. People today have a lot of alcohol.

C. People today have more tobacco.

D. Food today is quite different from that of ancient times.

2.Which of the following belongs to the dairy products?

A. Milk              B. Corn     C. Pork             D. Flour

3. New kinds of sicknesses have been found because ________.

A. the human body has changed compared with humans who first appeared on the earth

B. the way we live has changed a little

C. our body can’t deal with the changes in life style

D. the way we live today is proper for the human body

4. According to some scientists, Stone-age people were much healthier than people today because they ate a lot of ________.

A. milk and other dairy products                         B. salt and sugar

C. wild animals, fresh wild vegetables and fruits     D. grain foods

  根据短文内容，从短文后的选项中选出能填入空白处的最佳选项，并在答题卡上将该项涂黑。选项中有两项为多余选项。

Recently some American scientists have given a useful piece of advice to people in industrialized countries. They say people should eat more of the same kind of food eaten by humans living more than 10,000 years ago.    1  

The scientists say that human life has changed greatly. Our bodies have not been able to deal with these changes in lifestyle and this has led to new kinds of sicknesses.    2    They are called “diseases of civilization”. Many cancers and diseases of the blood system arc examples of such diseases.

    The scientists noted that people in both the Old Stone Age and the New Stone Age enjoyed very little alcohol or tobacco, probably none.    3    However, a change in food is one of the main differences between life in ancient times and that today.

Stone Age people hunted wild animals for their meat, which had much less fat than domestic（驯养的）ones. They ate a lot of fresh wild vegetables and fruits. They did not have milk or any other dairy products, and they made very little use of grains.    4    We eat six times more salt than our ancestors and we eat more sugar as well. We eat twice as much fat but only one third as much protein （蛋白质）and much less vitamin C.

   5    But the scientists say that we would be much healthier if we eat much the same way the ancient people did, cutting the amount of fat, salty and sweet food.

    A. Stone Age people lived a simple life without any meat.

    B. But today, we enjoy eating a lot of these.

    C. In that case, they would live a much healthier life.

    D. Ancient people also got lots of physical exercise.

    E. These new sicknesses were not known in ancient times.

    F. People today probably don’t want to live like our ancestors.

    G. Modern people used to suffer from “diseases of civilization”.