1、大学英语四级 267及答案解析(总分：746.58，做题时间：130 分钟)一、Writing (30 minutes)(总题数：1，分数：30.00)1.For this part, you are allowed thirty minutes to write a composition on the topic Getting to Know the World Outside the Campus. You should write at least 120 words and you should base your composition on the outline (given
2、 in Chinese) below: 1大学生了解社会的必要性 2了解社会的途径(大众媒介、社会服务等) 3我打算怎么做 （分数：30.00）_二、Reading Comprehensio(总题数：1，分数：71.00)A Mystery in the Lunchbox Hungry? Sit down. Were having catfish, corn on the cob, baked potatoes and fresh tomatoes. This might turn out to be the most nutritious meal of your life. It migh
3、t even be the best-tasting dinner you ever had. On the other hand, it might induce an allergic (过敏性的) reaction even though you are not allergic to any of these foods. Different Opinions about Biotechnology (生物工程) Products Last weeks announcement that the U.S. federal government would impose no speci
4、al regulations on bioengineered foods, in effect permitting them to be marketed exactly like natures own, proclaims a potentially vast change in our food supply. “We will not compromise safety one bit,“ Vice President Dan Quayle told the press. “And consumers will enjoy better, healthier food produc
5、ts at lower prices.“ Many specialists in biotechnology agree in fact, they see consumers around the world benefiting from a new, genetically-engineered green revolution but critics are urging the government to move ahead more cautiously. “We should have learned from the history of regulating pestici
6、des (杀虫剂) that we never knew the long-term consequences until it was too late,“ says Ellen Haas, executive director of Public Voice for Food and Healthy Policy, a Washington D.C.-based advocacy group. The Food and Drug Administration maintains that most bioengineered foods present no special safety
7、issues. “Were saying this is just another plant-breeding technique,“ says Eric Flamm, deputy director of the FDAs Office of Biotechnology. How Does Recombination of DNA Work? Heres how bioengineering works: all cells contain DNA, the long molecule (分子) shaped like a double helix (螺旋). A gene is a sw
8、atch (样本) of DNA that controls a certain characteristic of the organism. In the 1970s scientists discovered they could clip off a gene-length swatch from a DNA molecule, and later they learned to affix (固定) it to a different DNA molecule a cut-and-paste job that became known as gene splicing and res
9、ults in whats called recombinant DNA. Immediately, visions of carrots with the flavor of peanut butter began dancing in the imaginations of scientists and food writers alike. But most current experiments are less exotic (异乎寻常的). In many ways the new technology differs little from traditional crossbr
10、eeding. One Product of Bioengineered Technology The first example of recombinant DNA in a form suitable for lunch makes its debut (首次露面) next summer: the Flavr Savr tomato. Scientists at Calgene, Inc., a biotech company based in Davis, California, isolated the gene in the tomato that triggers the en
11、zyme (酶) responsible for rotting and rendered it inactive. Rather man having to be picked hard and green for easy shipping, the tomatoes stay on the vine about five days longer than usual. They can be shipped* without refrigeration, which also helps retain flavor, and theyll resist rotting for more
12、man three weeks, twice as long as their conventionally grown cousins. They arent perfect: like other supermarket tomatoes theyre grown with pesticides, they may be waxed, and they still lack the last three to five days of vine-ripening that homegrown tomatoes enjoy. Sampled at Calgenes headquarters,
13、 the Flavr Savr tasted fine; whether consumers still find it worth a dollar more per pound remains to be seen. Developing Pest Resistant Plant Several companies are hard at work on plants that will repel (抵制) pests (害虫). Monsanto, a St. Louis, Missouri, chemical company, expects to put many such pro
14、ducts on the market before the end of the decade. The weapon of choice is Bacillus thuringiensis, or BT, a soil-dwelling bacterium (细菌) that creates a protein crystal that is toxic to certain insects but harmless digested by humans. BT has been used for 30 years as an organic pesticide. Scientists c
15、an transfer the gene for the toxin into plant cells, and the new plants will produce their own insecticides. Like traditional insecticides, however, these may simply spur the creation of new, more resistant pests. According to Belknap, the solution will be to splice several toxins into a given plant
16、, thus lessening the potential for insects to develop resistance (or inviting the birth of some pretty amazing insects). One Member of the Herbicide (除草剂) Family, and Its Problems Monsanto is also developing herbicide-resistant plants, specifically Roundup-resistant plants. Roundup is one of Monsant
17、os most lucrative (获利的) products, a herbicide with sales of a billion dollars a year. It has been recognized as noncarcinogenic (非致癌的) by the Environmental Protection Agency, though its toxic to fish. Roundup is used as a weed-killer, but it will kill everything else it touches in the field, so farm
18、ers have had to apply it carefully. Now, however, Monsanto can isolate the enzyme in, say, corn, that is fatally vulnerable to Roundup. A corn plant engineered to have twice as much of that enzyme can lose a chunk of it to Roundup and still survive. Critics charge that this technology simply invites
19、 fanners to use more Roundup. Good News for the Business but Consumers Are Entitled to Know What They Are Eating Its not surprising that biotechnology companies were delighted by the FDAs green light. Environmentalists and other consumer advocates dont claim the new foods are unsafe by definition, b
20、ut they do call for tougher scrutiny (监督) than the FDA believes is necessary. “The regulations do a lot more to protect the industry than they do to protect the American consumers, “says Rebecca Goldburg, a senior scientist at the Environmental Defense Fund, an advocacy group. “The public has a righ
21、t to know whats in its food.“ Its Up to the Biotechnology Industry, not FDA Goldbury and other critics are especially concerned about potential allergens that may be hiding in new products an orange touched up with a gene from a cherry, for instance. The FDA requires no special testing or labeling u
22、nless the new food is substantially different from its traditional version. A new food containing a “common allergen“ would also have to be labeled, but as examples of common allergens the FDA suggests only eggs, milk, fish, shellfish, tree nuts, wheat and other legumes. The truth is, almost any foo
23、d is an allergen (过敏源) to someone. According to the FDA, its up to the biotechnology industry to police itself on potential allergens. “If you move a gene, you have to prove it not allergenic or you will have to label it,“ says Flamm. There Are Better Ways to Produce Food than Using Biotechnological
24、 Methods Other critics are uneasy about making such dramatic changes with such speed. “We ought to be testing these changes in large populations over large periods of time,“ says Greg Drescher, a director of Old-ways Preservation I came here for more noble reasons. I wanted a broad education that wo
25、uld provide me with flexibility and a value system to guide me in my career. I wanted to open my eyes and expand my vision by interacting with people who werent studying science or engineering. My parents, teachers and other adults praised me for such a sensible choice. They told me I was wise and m
26、ature beyond my 18 years, and I believed them. I headed off to college sure I was going to have an advantage over those students who went to big engineering “factories“ where they didnt care if you had values or were flexible. I was going to be a complete engineer: technical genius and sensitive hum
27、anist (人文学者) all in one. Now Im not so sure. Somewhere along the way my noble ideals crashed into reality, as all noble ideals eventually do. After three years of struggling to balance math, physics and engineering courses with liberal arts courses, I have learned there are reasons why few engineeri
28、ng students try to reconcile (协调) engineering with liberal-arts courses in college. The reality that has blocked my path to become the typical successful student is that engineering and the liberal arts simply dont mix as easily as I assumed in high school. Individually they shape a person in very d
29、ifferent ways; together they threaten to confuse. The struggle to reconcile the two fields of study is difficult. （分数：177.50）(1).The author chose to study engineering at a small liberal-arts university because he _.（分数：35.50）A.intended to be a sensible student with noble idealsB.wanted to be an exam
30、ple of practicality and rationalityC.intended to be a combination of engineer and humanistD.wanted to coordinate engineering with liberal-arts courses in college(2).According to the author, by interacting with people who study liberal arts, engineering students can _.（分数：35.50）A.broaden their horizo
31、nsB.become noble idealistsC.receive guidance in their careersD.balance engineering and the liberal arts(3).In the eyes of the author, a successful engineering student is expected _.（分数：35.50）A.to be imaginative with a value system to guide himB.to be a technical genius with a wide visionC.to have an
32、 excellent academic recordD.to be wise and mature(4).The authors experience shows that he was _.（分数：35.50）A.creativeB.irrationalC.ambitiousD.unrealistic(5).The word “they“ in “. together they threaten to confuse.“ ( Line 3, Para. 5) refers to（分数：35.50）A.practicality and rationalityB.engineering and
33、the liberal artsC.reality and noble idealsD.flexibility and a value systemSome people would say that the Englishmans home is no longer his castle, that it has become his workshop. This is partly because the average Englishman is keen on working with his own hands and partly because he feels, for one
34、 reason or another, that he must do for himself many household for which, some years ago, he would have hired professional help. The main reason for this is a financial one. The high cost of labour has meant that builders and decorators cost have reach a level which makes them prohibitive for housep
35、roud English-people of modest means. So, if they wish to keep their houses looking bright and smart, they have to tackle some of the repairs and decorating themselves. As a result, there has grown up in the post-war years what is sometimes referred to as the “ do-it-yourself movement“. The “do-it-yo
36、urself movement“ began with home decorating but has since spread into a much wider field. Nowadays there seem to be very few things that cant be made by the “do-it-yourself movement“ method. A number of magazines and handbooks exist to show hopeful handymen of all ages just how easy it is to build a
37、nything from a coffee table to a fifteen foot (4. 5 meters) sailing dinghy(小船). All you need, it seems, is a hammer and a few nails. You follow the simple instructions step by step and, before you know where you are, the finished article stands before you, completely in every detail. Unfortunately,
38、alas, it is not always quite as simple as it sounds! Many a budding(初露头角的) “do-it-yourself“ has found to his cost that one can not learn a skilled craftsmans job overnight. How quickly one realizes, when doing it oneself, that a job which takes the skilled man an hour or so to completely takes the a
39、mateur handyman five or six at least. And then there is the question of tools. The first thing the amateur learns is that he must have the right tools for the job. But tools cost money. There is also the wear and tear on the nerves. It is not surprising then that many people have come to the conclus
40、ion that the expense of paying professional to do the work is, in the long run, more economical than “ doing it oneself“. （分数：177.50）(1).Many Englishman join in the movement of “do-it-yourself,“ because_.（分数：35.50）A.they are skilled handymenB.they are proud of their housesC.they cant afford professi
41、onal helpD.they are men(2).Which of the following people can repair and decorate their own houses?（分数：35.50）A.Skilled craftsman.B.Handy of all ages.C.Hopeful men.D.Family supporters.(3).The “do-it-yourself“ movement originates in_.（分数：35.50）A.house repairingB.house buildingC.house decoratingD.furnit
42、ure building(4).Which of the following is false? Some Englishmen prefer hiring professional decorators, because_.（分数：35.50）A.they are wealthyB.the craftsmans job is quite complicatedC.the tools are expensiveD.do-it-yourself brings a lot of troubles(5).What is the suitable title of this passage?（分数：3
43、5.50）A.Englishmans Home.B.How to Do-It-Yourself.C.The High Cost of Labor.D.Do-It-Yourself Movement.八、Section B(总题数：1，分数：10.00)Just about everyone has been on a (47) 1 at one time or another, and millions of us have learned that the weight we lose is all too easily regained. Still few people question
44、 the wisdom of dieting. After all, we reason, the worst that can happen is that well regain the weight weve lostthen we can simply go on a diet again. But some new research suggests there is a risk: yo-yo dieting may seriously (48) 2 the bodys weight-control system. The more diets you go on, the har
45、der it may become to lose weight. Ever worse, new (49) 3 indicates that repeated (50) 4 of losing and gaining weight may raise the risk of heart problem. This last possibility is especially (51) 5. As part of a 25-year study that (52) 6 1959 men, researchers reported mat the men showing large up-and
46、-down weight changes had twice the risk of heart disease as those with only small changes in weight. One paper from the Framingham Heart Study, which has monitored more than 5000 people for 40 years, also provides troubling information: people who lose ten percent of their body weight had about 20 p
47、ercent (53) 7 in risk of heart diseasebut people who gained 150 to 135 pounds, and back to 150 again, could leave you with a higher heart-disease risk man you started with. None of this means that dieting is (54) 8 or foolish. For those who are 20 percent or more overweight, mere are good reasons to
48、 reduce: successful weight loss can (55) 9 blood pressure, help control blood sugar in diabetics(糖尿病患者) and enable people to feel better about themselves. But the new research does suggest that dieting must be taken seriously by people at any weight. It also means dieting alone is not the best way t
49、o weight control. When a weight-loss program includes exercise, you lose more fat and less muscle, and youre not likely to gain the weight back. Thats because exercise may help resist the (56) 10 changes that tend to come from yo-yo dieting. Word Bank A) concept B) reduction C) theory D) diet E) disturbing F) ineffective G) overall H) evidence I) physical J) monitored K)
