[外语类试卷]国家公共英语（四级）笔试模拟试卷180及答案与解析.doc

1、国家公共英语（四级）笔试模拟试卷 180及答案与解析 PART A Directions: For Questions 1-5, you will hear a conversation. While you listen, fill out the table with the information you have heard. Some of the information has been given to you in the table. Write only 1 word in each numbered box. You will hear the recording twi

2、ce. You now have 25 seconds to read the table below. 1 PART B Directions: For Questions 6-10, you will hear a passage. Use not more than 3 words for each answer. You will hear the recording twice. You now have 25 seconds to read the sentences and the questions below. 6 PART C Directions: You will he

3、ar three dialogues or monologues. Before listening to each one, you will have 5 seconds to read each of the questions which accompany it. While listening, answer each question by choosing A, B, C or D. After listening, you will have 10 seconds to check your answer to each question. You will hear eac

4、h piece ONLY ONCE. 11 Which of the following is not true of the Space Shuttle Columbia? （ A） It was the first rocket ever made in history. （ B） It did the first flight in 1981. （ C） Its first flight was of great importance in the development of space exploration. （ D） It can only stay in space for a

5、bout a week now. 12 Why is the Space Shuttle Columbia special? （ A） Because it is not similar to the spaceships of the previous twenty years. （ B） Because it has different designs and is able to return to earth and make further flights. （ C） Because it can be used in a variety of ways now. （ D） Beca

6、use it can be used to establish colonies on earth. 13 According to the talk, what will man probably be able to do by the year 2050? （ A） Establish a large number of projects in Space Shuttle Columbia. （ B） Build permanent colonies in space. （ C） Construct many energy stations on the islands in the s

7、ea. （ D） Build filling stations in space to provide fuel for cars on earth. 14 What was the purpose of the professors experiments? （ A） To find out how clever monkeys were. （ B） To test the intelligence of different animals. （ C） To compare the difference between man and the monkey. （ D） To find out

8、 how monkeys search for food. 15 Why did the professor put the food in a small box? （ A） To give the monkey a surprise. （ B） To see how the monkey ate from a box. （ C） To see how soon the monkey could find it. （ D） To find out how the monkey would open the box. 16 How did the professor watch the mon

9、key? （ A） By waiting outside the door. （ B） By waiting inside the door. （ C） By kneeling down at the door. （ D） By putting it in a small box. 17 What day of the week is it? （ A） Thursday. （ B） Friday. （ C） Saturday. （ D） Sunday. 18 What is Michael planning to do on Sunday afternoon? （ A） Go out with

10、 some friends. （ B） Show his sister and brother-in-law around. （ C） Sleep all afternoon. （ D） Go to a football game. 19 Why does the woman think it is good that the test will be early? （ A） They will have time to study for it. （ B） Afternoons are bad times for tests. （ C） After it, they can study fo

11、r other exams. （ D） They can start planning for their semester break. 20 Which of the following is probably true of the woman? （ A） She has no or few plans for the weekend. （ B） Shed like to go out with the man. （ C） She is going to be busy all Sunday. （ D） She is worried about her performance on th

12、e final. 一、 Section II Use of English (15 minutes) Directions: Read the following text. Choose the best word for each numbered blank and mark A, B, C or D on ANSWER SHEET 1. 20 We often hear the【 21】 “Bug“ while using computers. But what is a bug? In computer science, a bug【 22】 an error in software

13、 or hardware. In software, a bug is an error in coding or logic that causes a program to malfunction or to【 23】 incorrect results. Minor bugs, for example, a cursor that does not behave as【 24】 -can be inconvenient or frustrating, but not damaging to【 25】 More severe bugs can cause a program to “han

14、g“ (stop responding to【 26】 and might【 27】 the user with no【 28】 but to restart the program, losing whatever【 29】 work had not been saved. In【 30】 case, the programmer must find and correct the error by the【 31】 known as debugging. Because of the【 32】 risk to important data, commercial aplication pr

15、ograms are tested and【 33】 as completely as possible before release. Minor bugs found after the program becomes【 34】 are corrected in the next update; more【 35】 bugs can sometimes be fixed with special software, called patches, that circumvents or otherwise【 36】 its effects. In hardware, a bug is a

16、recurring【 37】 problem that prevents a system or set of【 38】from working together properly. The【 39】 of the term reputedly goes back to the early days of computing, when a hardware problem in a computer at Harvard University was【 40】 to a moth caught between the contacts of a relay in the machine. （

17、 A） wording （ B） term （ C） diction （ D） insect （ A） recurs to （ B） prefers to （ C） attributes to （ D） refers to （ A） produce （ B） achieve （ C） recreate （ D） attain （ A） expect （ B） expectation （ C） expecting （ D） expected （ A） information （ B） material （ C） memory （ D） news （ A） commands （ B） monito

18、r （ C） control （ D） supervision （ A） grant （ B） retain （ C） leave （ D） reward （ A） alternative （ B） objective （ C） collective （ D） derivative （ A） prestigious （ B） precarious （ C） previous （ D） precious （ A） both （ B） either （ C） neither （ D） none （ A） process （ B） operation （ C） performance （ D） ac

19、tion （ A） promising （ B） potential （ C） prospective （ D） probable （ A） debugged （ B） analyzed （ C） released （ D） removed （ A） accessible （ B） affable （ C） available （ D） adaptable （ A） minor （ B） major （ C） important （ D） severe （ A） alleviates （ B） worsens （ C） reduces （ D） enhances （ A） mental （ B

20、） physical （ C） formal （ D） substantial （ A） compounds （ B） compositions （ C） components （ D） composure （ A） beginning （ B） start （ C） source （ D） origin （ A） tracked （ B） traced （ C） followed （ D） detected Part B Directions: Read the following four texts. Answer the questions below each text by cho

21、osing A, B, C or D . Mark your answers on ANSWER SHEET 1. 40 We often hear advice from the dermatologists, “You should keep using sunscreen cream-just to be safe“. More and more people are questioning about sunscream. Can sunscreen cream help protect me against melanomas? How safe are we in applying

22、 these chemical cocktails? Does it actually stop melanomas, the most dangerous type of skin cancer, from forming? As is known to all, sunscreen cream can protect the skin from the harmful effects of sun. The most .important function of it is the prevention of skin cancer. A great number of American

23、people like to use it. Surprisingly, this kind of cancer is increasing in incidence faster than any other cancer in the United States. It seems that sunscreen actually increases the risk of skin cancer. More and more health experts are taking a discommendable attitude to the application of sunscreen

24、. Researchers show that the earlier finding has many flaws and is unable to prove the exact function because they fail to take into account many exceptional cases. For instance, some people prefer to use sunscreen cream while going out. However, sunscreen cream users suffer from cancer more often. I

25、n fact, sunscreen cream allows people to remain exposed in the sun longer. People are likely to get skin problem under the sunshine for a long time. Besides, many people use the sunscreen cream in an inappropriate way. The sunscreen cream should be applied about half an hour before going outside, so

26、 the time is enough for the sunscreen to soak in and take effect. In fact, the protection of sunscreen will not last indefinitely. It should be reapplied at least every two hours when people stay outdoors for a prolonged period. After swimming, bathing, perspiring heavily, or drying off with a towel

27、 or handkerchief, you had better reapply it, too. Millions of gallons of sunscreen cream are consumed each year. Only 5% of products overall met the criteria for safety and sunscreen effectiveness. Three of five brand-name products can not protect the skin from sun damage sufficiently or they contai

28、n hazardous chemicals, according to a report by Environmental Working Group (EWG). It is time to change our misunderstanding now. In fact, besides the sunshine-preventing function, it also has the function of protecting our skin. We all know that the sun impacts collagen production in the skin, and

29、without collagen, skin wont naturally maintain that plump, moist, youthful, wrinkle-free look. Without the protection of sunscreen cream, just a few minutes of daily sun exposure over the years can cause noticeable changes in skin. Sunscreen cream can protect our skin from these damaging rays, so th

30、at even if we do spend time outdoors, our face is less likely to give away our age. 41 What can we learn from the first paragraph? （ A） Sunscreen cream is essential in peoples life. （ B） The dermatologists prefer to attribute the skin problems to sunshine. （ C） People agree with the dermatologists o

31、pinion on using sunscreen cream. （ D） Sunscreen cream actually increases the risk of skin cancer. 42 Which of the following is true according to the passage? （ A） People could get skin problems using sunscreen cream. （ B） People had better not reuse sunscreen cream when they are outside. （ C） Sunscr

32、een cream can not function after a long period. （ D） We should abandon handkerchiefs to deal with skin problems. 43 The word “met“ in Paragraph Three, Line Two probably refers to （ A） see （ B） discover （ C） reach （ D） act 44 What is mainly discussed in the text? （ A） How to use sunscreen cream bette

33、r （ B） The different opinions on sunscreen cream （ C） Connection between cancer and sunscreen （ D） Research on the new functions of sunscreen cream 45 According to the text, what is not the attitude of the Writer? （ A） The writer has changed the prejudiced opinion on sunscreen cream. （ B） The writer

34、 advises people to use sunscreen cream regularly. （ C） The writer persuades the people to put the sunscreen to everyday use. （ D） The writer is supporting the new findings on sunscreen cream. 45 Bacteria are microscopic organisms which live on the surface of objects. They are one of the most ancient

35、 living things, which exist on this planet for nearly 4,000 million years. Do you know the size of bacteria? It can only be measured in microns. Maybe you have not a standard in your mind how long a micron is. One micron is a thousandth of a millimeter, which equals about the diameter of a pinhead.

36、Therefore, even if we enlarged the rounded bacterium a thousand times, it would only be the size of a pinhead. We barely see bacteria by a magnification an ordinary microscope of 100 times, even if we try, we cannot make out anything of their structure. There are normally millions of them together,

37、for they can multiply really fast. Scientists have found that some bacteria have attached to wavy-looking “hairs“ called flagella. The flagella rotate, pushing the bacteria through the water. Others can glide along over surfaces by some little-understood mechanism. Bacteria are so small that they ar

38、e influenced by the movements of the chemical molecules around them. They are active all the time. Even the bacteria without flagella often bound about in the water. They are pushed here and there, colliding with the watery molecules. Bacteria cannot be detected because they dont produce bad odor or

39、 change the color or texture of the food. Therefore, when people eat the food with many bacteria, they are likely to get hepatitis A, acute gastroenteritis and a host of other illnesses. Many households have refrigerators to prevent from bacteria. Of course, freezing food slows or stops the growth o

40、f bacteria, however, when food is thawed, the bacteria will become reactivated. Bacteria can not be totally destroyed before the food is thoroughly cooked. We need to know that not all bacteria are in connection with illness. Just some bacteria can cause disease. They are called pathogenic bacteria.

41、 Fortunately our immune system can protect us from them. Bacteria are prokaryotes ( single cells that do not contain a nucleus). It may seem weird to classify organisms according to such details, but with or without a nucleus is not trivial at all. The division between prokaryotes and eukaryotes (al

42、l organisms with a nucleus inside their cells) is of extreme importance in biology, and is the result of a major evolutionary breakthrough. Visit our program tomorrow if you want to know more, thank you. 46 Which of the following is true according to the first paragraph? （ A） Bacteria are as big as

43、a pinhead. （ B） Bacteria can not be seen by an ordinary microscope. （ C） Bacteria are hard to see because they often live together. （ D） Bacteria are very small so they can only be measured in microns. 47 Which statement is not true about flagella? （ A） Flagella are part of bacteria. （ B） Flagella h

44、elp bacteria to move. （ C） Flagella are always going round and round. （ D） Flagella are like waves. 48 What is the meaning of “collide“ in the second paragraph? （ A） strike （ B） connect （ C） bounce （ D） mix 49 Which of the following ways can help people prevent from bacteria? （ A） Smell and have a c

45、areful look at the food. （ B） Only eat the food stored in refrigerator. （ C） Ensure the food is totally heated before eating. （ D） Eat the food before they are thawed. 50 What can be inferred from the last paragraph? （ A） Whether or not to have a nucleus is important in biology. （ B） The speaker wil

46、l tell us how to distinguish bacteria tomorrow. （ C） Evolution will be the main topic of the program next time. （ D） Eukaryotes develop from prokaryotes. 50 As the volcano erupts in Iceland, more and more people are beginning to concern about the damage volcanic eruption brings. Then, let us learn t

47、he influence of volcanic eruption together. We all know that air pollution has an effect on the worlds average air temperature. Scientists declare that volcanic eruption leads to weather changes, which is similar to air pollution. How will volcanic eruption impact on weather? Volcanic eruption throw

48、s hundreds of millions tons of ash into the stratosphere. The ash from a volcano spreads in a few days. However, this is not the end. The ash will remain in the air for years. Hereby, all the ash turns incoming solar radiation into space, which cools the earth. The eruption would affect every level

49、of ecosystem, from worms to primates. The problem is not only the physical destruction of habitat, but also the sulfur gases over the area. The volcanic eruption makes many people homeless who have to search for food and residence everywhere. The movement of the population and refugees may lead to some instability in the region. They may become one part to damage the environment in face of starvation threat. If the lava pours into lakes, the water will be severely contaminated. The unusual accumulation of carbon dioxide in the lower strata of lakes basin may even cause explos