1、大学英语四级 18 及答案解析(总分：746.53，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 required to write a composition about “What Would Happen If There Were No Power“ in three paragraphs. You are given the first sentence or part of the first sentence of each paragraph. Your compositio
2、n should be nm less than 120 words. Remember to write your composition neatly. 1. Ever since early the last century, electricity has become an essential part of our modern life. _. 2. If there were no electric power, _. 3. Therefore, _. （分数：30.00）_二、Reading Comprehensio(总题数：1，分数：71.00)Cholesterol an
3、d Heart Disease Do you know your cholesterol level? Many people dont. A high level of cholesterol in the blood is an important risk factor for heart disease. Some people say that the danger of heart disease is exaggerated. However, heart disease is a main cause of death in developed countries. Every
4、 year more than one million Americans have heart attacks, and half of them die. People With heart disease suffer chest pains that make simple activities, such as walking, shaving, or taking a shower, difficult. Research has proven that cholesterol levels are Connected with heart disease. One project
5、 in Massachusetts has studied the same group of men and women since 1948. The researchers have found that the people who have high levels of cholesterol have more heart attacks. A natural substance in the blood, cholesterol comes from the liver. The amount of cholesterol is affected by diet and by p
6、hysical qualities we inherit from our parents. One kind of cholesterol sticks fat to the walls of arteries, making them smaller and finally blocking them. It produces a condition called “hardening of the arteries,“ which causes heart attacks. With tiny cameras, doctors can see blood circulating thro
7、ugh the heart valves. Angiograms (血管造影照片) are x-rays of the heart arteries. They show fat deposits and blockages caused by high cholesterol. Heart disease begins in children as young as 3 years old. It occurs earlier in boys than in girls. Nearly half of teenagers have some fat deposits on their art
8、ery walls. Heart disease develops faster if we have high cholesterol levels and also smoke. What is a safe level of cholesterol? Adults have a high risk of heart attack if their cholesterol level is above 240 milligrams per deciliter (1/10 公升) of blood. Below 200 is better. In the Massachusetts stud
9、y, no one with a cholesterol level below 150 has ever had a heart attack. However, about half of American adults have cholesterol levels above 200. To lower our cholesterol level, we must change our eating habits. Anything that comes from an animal is high in fat and high in cholesterol. The America
10、n Heart Association National Cholesterol Education Program says that fat should be no more than 30 percent of our diet. Blood cholesterol levels start to fall after 2 to 3 weeks of following a low-cholesterol, low-fat diet. Dietary changes alone can result in a 10 percent reduction of the average pe
11、rsons cholesterol level. Aerobic exercise helps, too. Artery blockage can be reduced by as much as 40 percent through changes in diet and amount of exercise. We must educate everyone, including children in elementary schools. We must teach them responsibility for their health through classes in nutr
12、ition and aerobic exercise. For example, the smart snack is fruit. Children must be served fruit in the school cafeteria, along with low-fat meals. Schools must send recipes home with the children. Parents must include children in planning and preparing meals and shopping for food. Adults, including
13、 persons over the age of sixty five, can lower their cholesterol by 30 or 40 percent. It is never too late to change. One man began his health program when he was seventy- three. By the time he was seventy-seven, he had lowered his arterial blockage from 50 percent to 13 percent and his cholesterol
14、from 320 to 145 without drugs. He went on a vegetarian diet with only 10 percent fat, plus programs to reduce stress and get more exercise. A low-cholesterol diet that cuts out most animal products and high-fat vegetables may be unfamiliar to people. The Heart Association says to use no added fat of
15、 any kind. Dont fry food in oil. Cook it in water, vinegar, or vegetable water. Learn about grains and vegetables. Avoid egg yolks (the yellow part of the egg). Eat potatoes, beans, low fat vegetables, and fruit. People often complain about low-fat diets before they have had time to get used to them
16、. Food can taste good without cream, butter, and salt. You can use olive oil, mustard, fresh herbs, or yogurt instead. A new diet can cause general anxiety, when people feel worried and nervous about what is going to happen. They must learn to deal with the changes in their lives. Sometimes major ch
17、anges in diet or lifestyle are easier than minor ones because the results are bigger and faster. Fast results encourage us. How can you control the amount of fat in your diet if you eat in restaurants? Restaurants must provide healthy meals that are low in fat, salt, and cholesterol. A diet is a per
18、sonal thing. Restaurant owners should not make customers feel embarrassed because they want to follow a diet that is good for them. Restaurant owners must learn to give equal service to customers on a healthy diet. Some restaurants have items on the menu marked with a heart to show that they are low
19、 in fat, cholesterol, salt, or sugar. A few restaurants serve only these recipes. Heart disease causes one out of every four deaths in East Harlem in New York City. The East Harlem Healthy Heart Program is an educational program. It has 2 goals: to get people to change their diets and to find volunt
20、eers to help run educational activities. One way it educates is by street shows. Actors wear costumes and carry big pieces of plastic fat. They entertain so people will listen. Groups of children perform songs and dances that educate people about heart disease and diet. Volunteers lead walking and e
21、xercise groups to show people how to begin exercising. Volunteers also stand in supermarkets to suggest healthy food choices to shoppers. The volunteers have shoppers taste two kinds of milk to see which tastes better. Most people are surprised that the low-fat milk tastes better than the whole milk
22、. Shoppers are encouraged to buy low-fat milk instead of whole milk. Education costs money, but it also brings results. In 1983, only 35 percent of the American public knew their cholesterol levels. By 1990, 65 percent of the people had had theirs checked. People feel better if they lower their chol
23、esterol through diet. Healthy people are more confident. They are more attractive to themselves, as well as to others. Their friends stare at them because they look so healthy. We can prevent heart disease by living a healthful lifestyle and eating the right kind of diet. If people dont do this, two
24、 out of three men and women in America will eventually get heart disease. （分数：71.00）(1).No direct relationship has been proven between high cholesterol levels and heart attacks. （分数：7.10）A.YB.NC.NG(2).Boys have a higher risk of developing heart disease than girls. （分数：7.10）A.YB.NC.NG(3).Old people s
25、houldnt bother to change their eating habits because its too late for it to do them any good. （分数：7.10）A.YB.NC.NG(4).Low-fat diets always taste bad. （分数：7.10）A.YB.NC.NG(5).It can be easier to change our diet a lot than to change it a little. （分数：7.10）A.YB.NC.NG(6).More than twice as many people had
26、their blood cholesterol levels checked in 1990 as in 1983 . （分数：7.10）A.YB.NC.NG(7).The article deals with the link between cholesterol and heart disease and the suggestions to pre- vent them. （分数：7.10）A.YB.NC.NG(8).Children should learn more responsibility or their health through 1. （分数：7.10）填空项 1:_
27、(9).One of the educational activities in East Harlem Healthy Heart Program is 1. （分数：7.10）填空项 1:_(10).Consumers are encouraged to buy low-fat milk rather than 1. （分数：7.10）填空项 1:_三、Listening Comprehens(总题数：1，分数：15.00)A.The man could buy a shirt of a different color.B.The size of the shirt is all righ
28、t for the man.C.The size the man wants will arrive soon.D.The man could come some time later.A.The woman is watching an exciting film with the man.B.The woman cant take a photo of the man.C.The woman is running toward the lake.D.The woman is filming the lake.A.Its quiet in the restaurant.B.The price
29、 is high in the restaurant.C.The restaurant serves good food.D.The restaurant is too far from their school.A.At a booking office.B.In a Hong Kong hotel.C.On a busy streetD.At an airport.A.The woman has been complaining too much.B.The womans headache will go away by itself.C.The woman should have see
30、n the doctor earlier.D.The woman should confirm her appointment with the doctor.A.Help the woman move the items.B.Hurry to Mr. Johnsons office.C.Help move things to Mr. Johnsons office.D.Put off his appointment with Mr. Johnson.A.The man should not dream of being a superstar.B.The man didnt practice
31、 hard enough.C.The man should find a new partner.D.The man should not give up.A.There is no more left.B.It doesnt appeal to her.C.Its incredibly delicious.D.She has already tasted it.A.The man is usually the last to hand in his test paper.B.The man has made a mess of his midterm exam.C.The man has b
32、ad study habits.D.The man is a diligent student.A.The man will drive the woman to school.B.The man has finished his assignment.C.The man is willing to help the woman.D.The man is losing patience with the woman.四、Section B(总题数：2，分数：10.00)A.With a knife.B.On the edge of some metal.C.On some glass.D.On
33、 a piece of paper.A.How much the cut hurt.B.How deep the cut was.C.How easily he was cut.D.How concerned the woman was.A.The amount of skin affected by the cut.B.The cause of the cut.C.The amount of bleeding.D.The number of nerve endings irritated.A.Since he was born.B.Since his early childhood.C.Tw
34、o years.D.Two months.A.Two months ago.B.Five months ago.C.Five years ago.D.Eight years ago.A.The long, cold winters.B.Bad traffic at peak times.C.Noise from garbage trucks.D.So many police officers on the street.A.Exhaustion.B.Cold weather.C.The job opportunity.D.The environment.A.A business corpora
35、tion.B.A society of legal professionals.C.The universe as a whole.D.An association of teachers and scholars.A.Its largest expansion took place during that period.B.Its role in society went through a dramatic change.C.Small universities combined to form bigger ones.D.Provincial colleges were taken ov
36、er by larger universities.A.Private donations.B.Grants from corporations.C.Government funding.D.Fees paid by students.A.California.B.Southern Alaska.C.The arctic.D.Europe.A.5,400,000 years.B.65,000,000 years.C.8,400,000 years.D.75,000,000 years.A.Tourists.B.Birds.C.Winds.D.Some animals.A.They wanted
37、 to follow his example.B.They fully supported his undertaking.C.They were puzzled by his decision.D.They were afraid he wasnt fully prepared.A.It is more exciting than space travel.B.It is much cheaper than space travel.C.It is much safer than space travel.D.It is less time-consuming than space trav
38、el.A.They both attract scientists attentionB.They can both be quite challengingC.They are both thought-provoking.D.They may both lead to surprising findings.A.To show how simple the mechanical aids for diving can be.B.To provide an excuse for his changeable character.C.To explore the philosophical i
39、ssues of space travel.D.To explain why he took up underwater exploration.六、Section C(总题数：1，分数：10.00)You probably have noticed that people express similar ideas in different ways, depending on the situation they are in. This is very (36) 1. All languages have two general levels of (37) 2: a formal le
40、vel and an informal level. English is no (38) 3. The difference in these two levels is the situation in which you use a (39) 4level. Formal language is the kind of language you find in textbooks, (40) 5books, and in business letters. You would also use formal English in compositions and (41) 6that y
41、ou write in school. Informal language is used in conversation with (42) 7, family members and friends, and when we write (43) 8notes or letters to close friends. Formal language is different from informal language in several ways. First, formal language tends to be more polite. (44) 9. For example,
42、I might say to a friend or family member, “Close the door, please, “(45) 10. Another difference between formal and informal language is some of the vocabulary. (46) 11. Lets say that I really like soccer. If Im talking to my friend I might say “Im just crazy about soccer!“ But if I were talking to m
43、y boss, I would probably say “I really enjoy soccer.“ （分数：10.00）填空项 1:_填空项 1:_填空项 1:_填空项 1:_填空项 1:_填空项 1:_填空项 1:_填空项 1:_填空项 1:_填空项 1:_填空项 1:_七、Reading Comprehensio(总题数：2，分数：355.00)Under proper conditions, sound waves will be reflected from a hillside or other such obstruction. Sound travels at the r
44、ate of about one-fifth of a mile per second. If the hill is eleven hundred feet away, it takes two seconds for the sound to travel to the hill and back. Thus, by timing the interval between a sound and its reflection (the echo), you can estimate the distance to an obstruction. During World War I1 th
45、e British used a practical application of this principle to detect German planes on their way to bomb London before the enemy was near the target. They used radio waves instead of sound waves, since radio waves can penetrate fog and clouds. The outnumbered Royal Air Force (RAF) always seemed to the
46、puzzled Germans to be lying in wait at the right time and never to be surprised (袭击). It was radio echoes more than anything else that won the Battle of Britain. Since the radio waves were used to tell the direction in which to send the RAF planes and distance to send them ( their range of flight, i
47、n other words), the device was called radio directing and ranging, and from the initials the word radar was coined. （分数：177.50）(1).Sound waves reflected from a hill can be used to estimate_.（分数：35.50）A.height of the hillB.speed of soundC.distance of the hillD.intensity of sound(2).The estimate is ba
48、sed on the_.（分数：35.50）A.direction of the hillB.accepted speed of soundC.interval between sound and echoD.both B and C(3).Practical application of this principle resulted in _.（分数：35.50）A.new electronic instruments for planesB.new radio sets for RAF bombersC.an electronic detecting deviceD.a radio directing and ranging device(4).Radar enabled the English _.（分数：35.50）A.detect German planes on their way to LondonB.direct the outnumbered RAF planes effective
