1、大学英语六级模拟试卷 764及答案与解析 一、 Part I Writing (30 minutes) 1 For this part, you are allowed 30 minutes to write a short essay entitled A Letter of Application. You should write at least 150 words following the outline given below: 1. 你即将大学毕业，申请出国攻读博士学位 2. 介绍个人简厉，所学专业以及专长 3. 公派出国，费用由中国政府提供 4. 希望申请被接受 二、 Par
2、t II Reading Comprehension (Skimming and Scanning) (15 minutes) Directions: In this part, you will have 15 minutes to go over the passage quickly and answer the questions attached to the passage. For questions 1-4, mark： Y (for YES) if the statement agrees with the information given in the passage;
3、N (for NO) if the statement contradicts the information given in the passage; NG (for NOT GIVEN) if the information is not given in the passage. 1 Genetically Modified Foods Feed the World? If you want to spark a heated debate at a dinner party, bring up the topic about genetically modified foods. F
4、or many people, the concept of genetically altered, high-tech crop production raises all kinds of environmental, health, safety and ethical questions. Particularly in countries with long agrarian (农业的 ) traditions and vocal green lobbies the idea seems against nature. In fact, genetically modified f
5、oods are already very much a part of our lives. A third of the corn and more than half the soybeans and cotton grown in the U.S. last year were the product of biotechnology, according to the Department of Agriculture. More than 65 million acres of genetically modified crops will be planted in the U.
6、S. this year. The genetic genie is out of the bottle. Yet there are clearly some very real issues that need to be resolved. Like any new product entering the food chain, genetically modified foods must be subjected to rigorous testing. In wealthy countries, the debate about biotech is tempered by th
7、e fact that we have a rich array of foods to choose from and a supply that far exceeds our needs. In developing countries desperate to feed fast-growing and underfed populations, the issue is simpler and much more urgent: Do the benefits of biotech outweigh the risks? The statistics on population gr
8、owth and hunger are disturbing. Last year the worlds population reached 6 billion. And by 2050, the UN estimates, it will be probably near 9 billion. Almost all that growth will occur in developing countries. At the same time, the worlds available cultivable land per person is declining. Arable land
9、 has declined steadily since 1960 and will decrease by half over the next 50 years, according to the International Service for the Acquisition of Agri-Biotech Applications (ISAAA). How can biotech help? Biotechnologists have developed genetically modified rice that is fortified with beta-carotene (胡
10、萝卜 素 ) which the body converts into vitamin A and additional iron, and they are working on other kinds of nutritionally improved crops. Biotech can also improve farming productivity in places where food shortages are caused by crop damage attributable to pests, drought, poor soil and crop viruses, b
11、acteria or fungi. Damage caused by pests is incredible. The European corn borer (螟虫 ) for example, destroys 40 million tons of the worlds corn crops annually, about 7% of the total. Incorporating pest-resistant genes into seeds can help restore the balance. In trials of pest-resistant cotton in Afri
12、ca, yields have increased significantly. So far, fears that genetically modified, pest-resistant crops might kill good insects as well as bad appear unfounded. Viruses often cause massive failure in staple crops in developing countries. Two years ago, Africa lost more than half its cassava (木薯 ) cro
13、p a key source of calories to the mosaic virus. Genetically modified, virus-resistant crops can reduce that damage, as can drought-tolerant seeds in regions where water shortages limit the amount of land under cultivation. Biotech can also help solve the problem of soil that contains excess aluminum
14、, which can damage roots and cause many staple-crop failures. A gene that helps neutralize aluminum toxicity (毒性 ) in rice has been identified. Many scientists believe biotech could raise overall crop productivity in developing countries as much as 25% and help prevent the loss of those crops before
15、 they are harvested. Yet for all that promise, biotech is far from being the whole answer. In developing countries, lost crops are only one cause of hunger. Poverty plays the largest role. Today more than 1 billion people around the globe live on less than 1 dollar a day. Making genetically modified
16、 crops available will not reduce hunger if farmers cannot afford to grow them or if the local population cannot afford to buy the food those farmers produce. Biotech has its own “distribution“ problems. Private-sector biotech companies in the rich countries carry out much of the leading-edge researc
17、h on genetically modified crops. Their products are often too costly for poor farmers in the developing world, and many of those products wont even reach the regions where they are most needed. Biotech firms have a strong financial incentive to target rich markets first in order to help them rapidly
18、 recoup the high costs of product development. But some of these companies are responding to needs of poor countries. More and more biotech research is being carried out in developing countries. But to increase the impact of genetic research on the food production of those countries, there is a need
19、 for better collaboration between government agencies both local and in developed countries and private biotech firms. The ISAAA, for example, is successfully partnering with the U.S. Agency for International Development, local researches and private biotech companies to find and deliver biotech sol
20、utions for farmers in developing countries. Will “Franken-foods“ feed the world? Biotech is not a panacea (治百病的药 ), but it does promise to transform agriculture in many developing countries. If that promise is not fulfilled, the real losers will be their people, who could suffer for years to come. T
21、he world seems increasingly to have been divided into those who favor genetically modified (GM) foods and those who fear them. Advocates assert that growing genetically altered crops can be kinder to the environment and that eating foods from those plants is perfectly safe. And, they say, genetic en
22、gineering which can induce plants to grow in poor soils or to produce more nutritious foods will soon become an essential tool for helping to feed the worlds burgeoning (迅速发展的 ) population. Skeptics contend that genetically modified crops could pose unique risks to the environment and to health risk
23、s too troubling to accept placidly. Taking that view, many European countries are restricting the planting and importation of genetically modified agricultural products. Much of the debate hinges on perceptions of safety. But what exactly does recent scientific research say about the hazards? Two ye
24、ars ago in Edinburgh, Scotland, eco-vandals stormed a field, crushing canola plants. Last year in Maine, midnight raiders hacked down more than 3,000 experimental poplar trees. And in San Diego, protesters smashed sorghum and sprayed paint over greenhouse walls. This far-flung outrage took aim at ge
25、netically modified crops. But the protests backfired: all the destroyed plants were conventionally bred. In each case, activists mistook ordinary plants for genetically modified varieties. Its easy to understand why. In a way, genetically modified crops now on some 109 million acres of farmland worl
26、dwide are invisible. You cant see, taste or touch a gene inserted into a plant or sense its effects on the environment. You cant tell, just by looking, whether pollen containing a foreign gene can poison butterflies or fertilize plants miles away. That invisibility is precisely what worries people.
27、How, exactly, will genetically modified crops affect the environment and when will we notice? Advocates of genetically modified or transgenic crops say the plants will benefit the environment by requiring fewer toxic pesticides than conventional crops. But critics fear the potential risks and wonder
28、 how big the benefits really are. “We have so many questions about these plants,“ remarks Guenther Stotzky, a soil microbiologist at New York University. “Theres a lot we dont know and need to find out.“ As genetically modified crops multiply in the landscape, unprecedented numbers of researchers ha
29、ve started fanning into the fields to get the missing information. Some of their recent findings are reassuring; others suggest a need for vigilance. 2 How much corn planted in the U.S. last year was genetically modified? （ A） More than half. （ B） 65 million acres. （ C） One third. （ D） Three quarter
30、s. 3 Why is the debate on genetically modified foods more heated in developing countries? （ A） They have a rich range of foods. （ B） They like traditional and natural food. （ C） They have to feed fast-growing populations. （ D） The risks of GM food outweigh the benefits. 4 Biotech can improve product
31、ivity, which can be proved by trials of_. （ A） pest-resistant cotton in Africa （ B） the European corn borer （ C） the genetically modified rice （ D） vitamin A much more converted 5 What have scientists done to solve the problem of soil that contains excess aluminum? （ A） They have engineered the crop
32、s to be virus-resistant. （ B） They have found a gene to fight the excess toxicity. （ C） They have modified the crops to be drought-tolerant. （ D） They have improved the soil by absorbing excess aluminum. 6 The most important factor that leads to hunger in developing countries is_. （ A） lost crops （
33、B） global greenhouse effect （ C） economic crisis （ D） poverty 7 Biotech firms have not much interest in the developing world market because_. （ A） running business there needs much in distribution （ B） farmers there are too poor to buy their products （ C） these firms want to keep their technology se
34、cret （ D） farmers there dont like genetically modified crops 8 Advocates of transgenic crops claim that_. （ A） these crops have no harm to the environment in their growing （ B） food from these crops are healthier than from the conventional （ C） these crops will certainly replace the conventional （ D
35、） these crops can greatly help to feed the world 9 Eco-vandals in Edinburgh stormed a field two years ago, aiming at_. 10 Raiders missed the genetically modified varieties because of the_of such plants. 11 Guenther Stotzky is afraid of the transgenic crops because of_. Section A Directions: In this
36、section, you will hear 8 short conversations and 2 long conversations. At the end of each conversation, one or more questions will be asked about what was said. Both the conversation and the questions will be spoken only once. After each question there will be a pause. During the pause, you must rea
37、d the four choices marked A, B, C and D, and decide which is the best answer. （ A） Husband mad wife. （ B） Doctor and nurse. （ C） Sales clerk and customer. （ D） Airline agent and customer. （ A） Hes a secretary. （ B） Hes a novelist. （ C） Hes a newspaperman. （ D） Hes a worker. （ A） On a mountain path.
38、（ B） In a supermarket. （ C） On a mad. （ D） In a railway, station. （ A） Monday morning （ B） Monday afternoon. （ C） Wednesday morning. （ D） Friday afternoon. （ A） To encourage them. （ B） To stop them immediately. （ C） To give some explanation. （ D） To leave them alone. （ A） She has bad study habits. （
39、 B） She sleeps too much. （ C） She wakes up late. （ D） Shes an excellent student （ A） 4 hours. （ B） 6 hours. （ C） 12 hours. （ D） 18 hours. （ A） How primitive people used flags. （ B） What the ancient means of communication was. （ C） Why the torch towers were built. （ D） How the Great Wall came into be
40、ing. （ A） Neutral. （ B） Cautious. （ C） Favorable. （ D） Negative. （ A） It gives us sufficient information. （ B） It gives misleading information. （ C） It lets us know the best product. （ D） It fails to convince people. （ A） Advertisers. （ B） Manufacturers. （ C） Customers. （ D） Sellers. （ A） Hes offeri
41、ng some suggestions about learning foreign languages. （ B） Hes asking the woman for help to improve his English. （ C） Hes discussing with the woman how to listen to a language regularly. （ D） Hes talking about the importance of taking notes in foreign languages learning. （ A） By listening to documen
42、taries. （ B） By watching TV commercials. （ C） By watching foreign movies. （ D） By listening to foreign songs. （ A） Pronunciation. （ B） Culture. （ C） New words. （ D） Grammar. （ A） It helps one speak the language immediately. （ B） It helps one improve reading skill. （ C） It helps one improve writing s
43、kill. （ D） It helps one enlarge vocabulary. Section B Directions: In this section, you will hear 3 short passages. At the end of each passage, you will hear some questions. Both the passage and the questions will be spoken only once. After you hear a question, you must choose the best answer from th
44、e four choices marked A, B, C and D. （ A） Sea water. （ B） Coals. （ C） Steam. （ D） Electricity. （ A） 1812. （ B） 1862. （ C） 1912. （ D） 1962. （ A） Everyone would build a ship model to celebrate the day. （ B） Everyone was asked to wear clothes of the last century on that day. （ C） An identical ship woul
45、d make a voyage of Comets original route. （ D） All the citizens would join a grand parade to commemorate the day. （ A） Special ancestry and genetic structures （ B） Physical and cultural behaviors （ C） Mental and physical movements （ D） Mental behaviors and genetic structures （ A） Humans dont have th
46、e common ancestry with other simpler animals. （ B） Humans and apes are the dominant animals on the Earth. （ C） Humans and apes share 96% genetic structure. （ D） Respiration of humans is nearly the same with that of ducks. （ A） Their languages are too simple. （ B） Animals cant domesticate other being
47、s. （ C） Animals cultures dont have a long history. （ D） Animals cant share their cultures with other beings. （ A） Peoples indulgences in small pleasures. （ B） Peoples guilty feelings about indulgences. （ C） The enjoyment from physical pleasures. （ D） The worlds greatest pleasure takers. （ A） Doing p
48、hysical exercises. （ B） Eating high-fat foods. （ C） Drinking alcohol. （ D） Smoking. （ A） Australia. （ B） Belgium. （ C） Germany. （ D） Holland. （ A） They might feel less depressed. （ B） They might improve their immune system. （ C） They might give up all pleasures. （ D） They might be more likely to bec
49、ome sick. Section C Directions: In this section, you will hear a passage three times. When the passage is read for the first time, you should listen carefully for its general idea. When the passage is read for the second time, you are required to fill in the blanks numbered from 36 to 43 with the exact words you have just heard. For blanks numbered from 44 to 46 you are required to fill in the missing information. For these blanks, you can either use the exact words y
