[外语类试卷]大学英语四级模拟试卷317及答案与解析.doc

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1、大学英语四级模拟试卷 317及答案与解析 一、 Part I Writing (30 minutes) 1 For this part, you are allowed thirty minutes to write a composition on the topic( the title of the composition ). You should write at least 120 words, and base your composition on the outline (given in Chinese ) below. 假设你是学生会的成员，了解到不久前四川东部某地区发生

2、了地震，由于地震的影响人们无家可归。为了能帮助当地的人民迅速走出低谷，请你发出一封倡议书呼吁广大同学捐款捐物 . 二、 Part 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 1-7, mark： Y (for YES) if t

3、he statement agrees with the information given in the passage; 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 What Causes Cancer? The question “What causes cancer?“ has been asked for centuries. The s

4、hort answer is: we still dont know. But a tremendous amount has added to our understanding in recent decades. One major change in the way researchers view cancer is that they now rarely think in terms of a single unitary cause. Rather, it appears that most cancers are caused by the interaction of se

5、veral factors. In ninny cases, some or all of three factors may be involved: (1) viruses, (2) individual susceptibility, and (3) environmental irritants(刺激物 ). Another major change in our contemporary view of cancer is that it is now regarded as a premiere example of an environmental disease-that is

6、, a disease in which environmental factors are often crucial to the disease process. VIRUSES A number of viruses have been identified that induce cancer in laboratory animals. What about humans? As of the late 1970s, no virus had been shown conclusively to cause cancer in people. However, the scient

7、ific consensus was that it was probably only a matter of time before such a connection was proven. Cancer, however, is not a communicable disease, like a cold or influenza. It is not “catching“ in the ordinary sense of a word, and the mere presence of the suspect virus is apparently not enough, by i

8、t self, to produce the disease. It appears that the process may work something like this: A carcinogenic virus enters a cell and insinuates itself amidst the cells genetic material. (Viruses and genes are structurally similar. ) The virus may then lie dormant(休眠的 ) for years, until it is triggered i

9、nto action by some kind of environmental irritant, such as pollution or radiation. At that point, the reactivated virus causes changes in the genes, altering the host cell permanently and also altering all the cells produced by the division of the original cell. The genetic program of these newand n

10、ow cancerous-cell calls for tile unrestrained growth, dedifferentiation(分化 ), anaphase, and metastasis(转移 )discussed earlier. INDIVIDUAL SUSCEPIBILITY Some people may be more prone to develop cancers than others, for several possible reasons. Heredity is one. Resistance to cancer, or susceptibility

11、to it, is a quality for which laboratory animals can be bred. So, presumably, heredity may play some role in humans as well. Statistical evidence, however, shows only a minor tendency for cancers to run in families. Indeed, for most cancers no such tendency can be demonstrated. Cancers of the breast

12、, lung, thyroid, colon, and rectum do seem to cluster in families, at least to some degree. If your family has a history involving one of these cancers, you and your physician may want to be especially vigilant for signs of such cancer during your periodic physical examinations. Some researchers hav

13、e proposed that personality characteristics may render some people more vulnerable to cancer. According to this theory, people are more likely to develop cancer, and more likely to die from it, if they have rigid, authoritarian personality and suppressed inner conflicts about sexual and aggressive f

14、eelings. There have been many studies attempting to test this theory, and the results are thought-provoking. In one study, for example, doctors at the University of Rochester were able to predict with seventy-five percent accuracy whether women entering the hospital for a biopsy would have cancer or

15、 not, based on psychiatric interviews. However, this and many other studies linking cancer and psychological factors were performed on small samples. Well-controlled, large-scale, long-term studies are needed before the theory can be regarded as well established. A third factor that might influence

16、your susceptibility to cancer is the state of your immune system. When a persons immune system is weak, he or she has a heightened chance of developing cancer. The immune system can be weakened by a hereditary defect, by exposure to radiation, or by the action of immunosuppressive drags (given, for

17、example, to people who have organ transplants). ENVIRONMENTAL IRRITANTS You may have been surprised to learn that environmental factors play a role in funning sixty percent of cancer. You may also wonder: how do we know? We know, in large part, by studying the geographical patterns of cancer,! Lung

18、cancer, for example, is common in the United States and Britain, rare in Africa and most of Asia. Colon and rectal cancers are common in the West, but rare in developing countries. Rates of various cancers also vary dramatically in various regions of the United States. You might think that genetic o

19、r ethnic factors could account for these geographical differences. But careful studies of people who move from one country to another showed that immigrant populations quickly lost the patterns in their country of origin and developed the cancer patterns typical of their new environment. If more evi

20、dence is needed that environmental irritants play a major role in the development of cancer, it is abundantly supplied by the relationship between certain occupation and certain types of cancer. People who work with asbestos have high rates of lung cancer; so do uranium miners and people who tend co

21、ke(焦炭 ) ovens at steel mills. People who work with aniline dyes or in the rubber industry have elevated rates of bladder cancer. Being exposed to substances such as metals, dust, chemicals, or pesticides at work can increase the risk of cancer. Asbestos, nickel, cadmium, uranium, radon, vinyl chlori

22、de, benzidine, and benzene are well-known examples of carcinogens(致癌物 ) in the workplace. These may act alone or along with another carcinogen, such as cigarette smoke. For example, inhaling asbestos fibers increases the risk of lung diseases, including cancer, and the cancer risk is especially high

23、 for asbestos workers who smoke. It is important to follow work and safety rules to avoid contact with dangerous materials. Exposure to large doses of radiation from medical X-rays can increase the risk of cancer. X-rays used for diagnosis expose you to very little radiation and the benefits nearly

24、always outweigh the risks. However, repeated exposure can be harmful, so it is a good idea to talk with your doctor or dentist about the need for each X-ray and ask about the use of shields to protect other parts of your body. Before 1950, X-rays were used to treat noncancerous conditions (such as a

25、n enlarged thymus, enlarged tonsils and adenoids, ringworm of the scalp, and acne) in children and young adults. People who have received radiation to the head and neck have a higher-than-average risk of developing thyroid cancer years later. People with a history of such treatments should report it

26、 to their doctor and should have a careful exam of the neck every 1 or 2 years. In some of these instances, it is possible to pinpoint a particular environmental irritant, such as asbestos or polyvinyl chloride, which is involved in the process of cancer development. In the population at large, howe

27、ver, it is a guessing game trying to ascertain which pollutants and other substances to which we are exposed, or which combinations of these substances contribute to cancer. Are the major offenders in the water we drink? In the meat we eat? In the air we breathe? For the most part, we simply dont kn

28、ow. There are so many variables that analysis is extremely difficult. 2 Research into the causes of cancer reveals that we are still unsure of its precise causes. （ A） Y （ B） N （ C） NG 3 All the viruses have been identified that induce cancer in animals. （ A） Y （ B） N （ C） NG 4 Cancer is a communica

29、ble disease. （ A） Y （ B） N （ C） NG 5 The virus may then he inactive for years. （ A） Y （ B） N （ C） NG 6 All the cancers do seem to cluster in families, at least to some degree. （ A） Y （ B） N （ C） NG 7 Family heredity is related to certain types of cancer. （ A） Y （ B） N （ C） NG 8 It is possible to asc

30、ertain which pollutants and other substances to which we are exposed, or which combinations of these substances contribute to cancer in the future. （ A） Y （ B） N （ C） NG 9 _play a major role in the development of cancer. 10 An American steelworker has the high risk of_. 11 The intent of the author i

31、n writing this passage is to_readers. Section A Directions: In this 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

32、 each question there will be a pause. During the pause, you must read the four choices marked A, B, C and D, and decide which is the best answer. （ A） He is very hardworking. （ B） Hell miss the meeting that afternoon. （ C） Hell have an appointment with the hostess. （ D） He wont miss tile meeting. （

33、A） He is in need of qualified staff. （ B） He is doing quite well with it. （ C） He has money problem now. （ D） He can not carry it on any more. （ A） He has a serious disease. （ B） Hes too poor. （ C） Hes getting old. （ D） Hes overworked. （ A） He doesnt think about them. （ B） He likes them very much. （

34、 C） He thinks they arc not as good as many people expected. （ D） He doesnt like them. （ A） She wants to spend more time with her family. （ B） She thinks the pay is too low to support her family. （ C） She doesnt think she is capable of doing the job. （ D） She doesnt enjoy business trips as much as sh

35、e used to. （ A） The warm weather. （ B） A bright shirt. （ C） Things to wear. （ D） The best material for making clothes. （ A） In about four days. （ B） About two weeks from now. （ C） In four weeks. （ D） She hasnt decided yet. （ A） She doubts he makes much money now. （ B） She doesnt know when his classe

36、s started. （ C） Shes surprised he chose that agency. （ D） She wonders why hes kept his job. （ A） How to deal with the problems in a family. （ B） How to ask a neighbour to turn down the music. （ C） How to get along with those not so likable neighbours. （ D） How to compromise with the management of on

37、es building. （ A） Call the police to solve the problem. （ B） Come up with a compromise which works for both. （ C） Talk with the neighbour and explain the problem. （ D） Establish a good relationship with the neighbour. （ A） Five. （ B） Four. （ C） Three. （ D） Two. （ A） In a tube in New York. （ B） On a

38、train to New York. （ C） In a car in Florida. （ D） On a train to Florida. （ A） Neighbours. （ B） Acquaintances. （ C） Colleagues. （ D） Fellow passengers. （ A） He is afraid of being alone in New York. （ B） He retired because he wanted to see his grandchildren. （ C） He doesnt want to live alone in Florid

39、a. （ D） He wants to make friends after retirement. （ A） The woman has a family of three grandchildren in New York. （ B） The woman enjoys going to the theatre with her friends. （ C） The man has several close friends in Florida. （ D） The man will live in New York for a short period of time. Section B

40、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 the four choices marked A, B, C and D. （ A） To discover

41、the students study habits. （ B） To discover how many students wanted to get married. （ C） To discover the subjects that the students were interested in. （ D） To discover the students opinions on some matters of personal concern. （ A） The qualities a partner should have. （ B） The ideal age to get mar

42、ried. （ C） The ideal number of children. （ D） Favourite colour. （ A） Most students favour 26 to 30 as the ideal age to get married to an intelligent partner, and producing 2 children. （ B） Most students favour 21 to 25 as the ideal age to get married. （ C） Most students favour 26 to 30 as the ideal

43、age to get married to an attractive partner. （ D） Most students favour 21 to 25 as the ideal age to get married to an intelligent partner, and producing 3 children. （ A） Prior to the individuals 20th birthday. （ B） Prior to the individuals 2nd birthday. （ C） Prior to the individuals 22nd birthday. （

44、 D） Prior to the individuals 23rd birthday. （ A） Because their life was affected by their disabilities. （ B） Because they did not have enough courage to live on. （ C） Because they were denied civil rights. （ D） Because the medical treatment was not available to them. （ A） No protection available in

45、civil rights laws. （ B） Significant barriers in transportation and public awareness. （ C） Unemployment. （ D） Low social status. （ A） Higher productivity and a higher average income. （ B） Higher productivity but a lower average income. （ C） Lower productivity but a higher average income. （ D） Lower p

46、roductivity and a lower average income. （ A） It lies in the economists attitudes to population. （ B） It lies in the level of education. （ C） It lies in the official attitudes to population growth. （ D） It lies in the level of civilization. （ A） Because it results in a declining market for manufactur

47、ed goods. （ B） Because it results m rising prices. （ C） Because it results in rising demands. （ D） Because it results in pressure on housing. （ A） To control birth or not. （ B） Comparison between large population and small population. （ C） A large population may lead to higher employment. （ D） The a

48、dvantages and disadvantages of a large population. 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

49、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 you have just heard or write down the 36 From the invention of the first stone tools to todays complex computers, man has【 B1】 _the power to change the world around him. Computer【 B2】 _, in particular, could be taking over our economic life. In business, computers do the job of【 B3】 _and