2009年12月20日大学英语四级(CET-4)模拟试卷7.doc

2009年12月20日大学英语四级(CET-4)模拟试卷7Part WritingDirections: for this part, you are allowed thirty minutes to write a composition on the topic: Are Families Demanding Too Much from Their Children? You should write at least 120 words following the outline given below in Chinese: Are Families Demanding Too Much from Their Children?1. 有人认为知识产权保护很重要2. 有人认为盗版更实际3. 你的看法或：1. 越来越多的人关注动物福利2. 也带来一些矛盾3. 你的看法Part Reading Comprehension (Skimming and Scanning)Directions: In this part, you will have 15 minutes to go over the passage quickly. Y (for YES) if the 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. For questions 8 -10, complete the sentences with information given in the passage. Nuclear power plants provide about 17 percent of the worlds electricity. Some countries depend more on nuclear power for electricity than others. In France, for instance, about 75 percent of the electricity is generated from nuclear power, according to the International Atomic Energy Agency. In the United States, nuclear power supplies about 15 percent of the electricity overall, but some states get more power from nuclear plants than others. There are more than 400 nuclear power plants around the world, with more than 100 in the United States. Have you ever wondered how a nuclear power plant works or how safe nuclear power is? In this article, we will examine how a nuclear reactor and a power plant work. Uranium Uranium is a fairly common element on Earth, which was taken into the planet during the planets formation. Uranium is originally formed in stars. Old stars exploded, and the dust from these shattered stars aggregated together to form our planet. Uranium-238 (U-238) has an extremely long life (4.5 billion years), and therefore is still present in fairly large quantities. U-238 makes up 99 percent of the uranium on the planet. U-235 makes up about 0.7 percent of the remaining uranium found naturally, while U-234 is even rarer and is formed by the decay of U-238. Nuclear Fission (裂变) A nuclear fission happens when a uranium-235 nucleus with a neutron captures another neutron. The nucleus then splits into two lighter atoms and throws off two or three new neutrons (the number of ejected neutrons depends on how the U-235 atom happens to split). The two new atoms then produce gamma radiation as they settle into their new states. There are three things about this induced fission process that make it especially interesting: The probability of a U-235 atom capturing a neutron as it passes by is fairly high. In a reactor working properly (known as the critical state), one neutron ejected from each fission causes another fission to occur. The process of capturing the neutron and splitting happens very quickly, on the order of picoseconds (11012seconds). An incredible amount of energy is released, in the form of heat and gamma radiation, when a single atom splits. The two atoms that result from the fission later release beta radiation and gamma radiation of their own as well. The energy released by a single fission comes from the fact that the fission products and the neutrons, together, weigh less than the original U-235 atom. The difference in weight is converted directly to energy at a rate governed by the equation E = mc2. In order for these properties of U-235 to work, a sample of uranium must be enriched so that it contains 2 percent to 3 percent or more of uranium-235. Three-percent enrichment is sufficient for use in a civilian nuclear reactor used for power generation. Weapons-grade uranium is composed of 90-percent or more U-235. Inside a Nuclear Power Plant To build a nuclear reactor, what you need is some mildly enriched uranium. Typically, the uranium is formed into pellets (芯块) with approximately the same diameter as a coin and a length of an inch or so. The pellets are arranged into long rods, and the rods are collected together into bundles. The bundles are then typically submerged in water inside a pressure vessel. The water is used to lower the heat. In order for the reactor to work, the bundle, submerged in water, must be slightly supercritical. That means that, left to its own devices, the uranium would eventually overheat and melt. To prevent this, control rods (棒) made of a material that absorbs neutrons are inserted into the bundle. Raising and lowering the control rods allow operators to control the rate of the nuclear reaction. When an operator wants the uranium core to produce more heat, the rods are raised out of the uranium bundle. To create less heat, the rods are lowered into the uranium bundle. The rods can also be lowered completely into the uranium bundle to shut the reactor down in the case of an accident or to change the fuel. The uranium bundle acts as an extremely high-energy source of heat. It heats the water and turns it to steam. The steam drives a steam turbine, which spins a generator to produce power. In some reactors, the steam from the reactor goes through a secondary, intermediate heat exchanger to convert another loop of water to steam, which drives the turbine. Outside a Nuclear Power Plant Once you get past the reactor itself, there is very little difference between a nuclear power plant and a coal-fired or oil-fired power plant except for the source of the heat used to create steam. The reactors pressure vessel is typically housed inside a concrete liner that acts as a radiation shield. That liner is housed within a much larger steel containment vessel. This vessel contains the reactor core as well the hardware that allows workers at the plant to refuel and maintain the reactor. The steel containment vessel is intended to prevent leakage of any radioactive gases or fluids from the plant. Finally, the containment vessel is protected by an outer concrete building that is strong enough to survive such things as crashing jet airliners. These secondary containment structures are necessary to prevent the escape of radiation/radioactive steam in the event of an accident like the one at Three Mile Island. The absence of secondary containment structures in Russian nuclear power plants allowed radioactive material to escape in an accident at Chernobyl. What Can Go Wrong Well-constructed nuclear power plants have an important advantage when it comes to electrical power generation-they are extremely clean. Compared with a coal-fired power plant, nuclear power plants are a dream come true from an environmental standpoint. A coal-fired power plant actually releases more radioactivity into the atmosphere than a properly functioning nuclear power plant. Coal-fired plants also release tons of carbon, sulfur and other elements into the atmosphere. Unfortunately, there are significant problems with nuclear power plants: Mining and purifying uranium has not, historically, been a very clean process. Improperly functioning nuclear power plants can create big problems. The Chernobyl disaster is a good recent example. Spent fuel from nuclear power plants is toxic (有毒的) for centuries, and, as yet, there is no safe, permanent storage facility for it. Transporting nuclear fuel to and from plants poses some risk, although to date, the safety record in the United States has been good. These problems have largely derailed the creation of new nuclear power plants in the United States. Society seems to have decided that the risks outweigh the rewards. 1. There are over 400 hundred nuclear power plants in the world, most of the them are in Europe. 2. Scientists believe that uranium was absorbed by the Earth when it was formed. 3. The German government has decided to reduce its dependence on electricity generated by nuclear power. 4. A nuclear fission is a process of a U-235 nucleus with a neutron trying to capture another neutron. 5. Uranium has to be enriched if a nuclear reactor is built. 6. Control rods in a nuclear reactor are used to control the amount of energy generated in a nuclear reactor. They can also be used to shut the reactor or to change the fuel. 7. Mining and purifying uranium do not cause any environmental damage. 8. A nuclear reactor is protected by _, a concrete radiation shield, a steel containment vessel, and an outer concrete building. a pressure vessel 9. The result of nuclear fission is to release energy in the form of _. 10. The present solution to dispose _ is yet to be found as it remains toxic for a fairly long time. Part Listening ComprehensionSection ADirections: 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 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. Then mark the corresponding letter on Answer Sheet 2 with a single line through the centre.Question 11 to 18 are based on the conversation you have just heard. 11. A Go to the football match with the woman.B Ask the woman to help him write the term paper on history.C Finish the last tow chapters of history assignment.D Take part in the football match.12. A she wants to borrow the mans student cardB the tickets are less expensive than she expectedC she wont be able to get any discount for the ticketD the performance turns out to be disappointing13. A its far from being ready B it contains some valuable ideasC she needs another week to get it ready D it has nothing to do with the internet14. A He is suffering from the difference of time zones.B He has been studying hard at night.C He finds biology difficult to learn.D He has not adjusted to a new culture.15. A A lesson requires students active involvementB students usually take an active part in a lectureC more knowledge is covered in a lectureD there is a larger group of people interested in lesson16.A The pictures of night view are really better than he expectedB He didnt know how he finished his role in the playC The film hasnt been processed yetD He didnt have enough film17. A He often complains. B he is a short person.C He is worried about something. D He is a happy sort of person.18. A He cant miss the bank. B She forgot to tell him one thing.C Its no use going there. D The bank is close to the corner.Questions 19-21 are based on the conversation you have just heard19. A A vacation trip to Yellowstone ParkB A lecture by a visiting professorC Her biology thesisD A research project on Yellowstone Park20. A More buffalo are surviving the winterB Fewer buffalo are dying of diseaseC More buffalo are being bornD Fewer buffalo are being killed by hunters21. A She is from Wyoming and eager to visit Yellowstone ParkB She needs the money to continue her studyingC She has been studying animal diseasesD Her thesis adviser is heading the projectQuestions 22-25 are based on the conversation you have just heard.22.A) She knew about it by reading a booklet.B) She knew about it by reading a student union introduction.C) She knew about it by reading a newspaper.D) She knew about it by reading a magazine.23.A) Because they want to preserve the natural beauty of the campus.B) Because they want to protect the studentsright for living space.C) Because they want to conserve the place for future use.D) Because they want to sell the place for a better price.24. A) They will organize a meeting to discuss a proposal.B) They will organize a protest to express their opposition.C) They will organize an appeal-letter signing activity.D) They will organize a march around the campus.25. A) She will participate in the protest.B) She will sign the appeal letter.C) She will take part in a meeting of the Student Action Union.D) She will attend her class as usual.Section BDirections: 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). Then mark the corresponding letter on the Answer Sheet 2 with a single line through the centre.Passage OneQuestions 26 to 28 are based on the passage you have just heard.26. A How much exercise they get every day?B What they are most worried about?C How long their parents accompany them daily?D What entertainment they are interested in?27. A get enough entertainmentB have more activitiesC receive early educationD have regular checkups28. A be no place for playB be near a common areaC have no TV setsD have a computer for studyPassage TwoQuestions 29-32 are based on the passage you have just heard.29. A) To look for two of her close friends.B) To stay at home and study.C) To share an apartment with friends.D) To move out and live alone.30. A) She couldnt find a good place to stay.B) Her friend and she couldnt afford the rent.C) A friend left her for works sake.D) She quarreled with her friends.31. A) Because her home was far way from school.B) Because her parents asked her to do so.C) Because she was bored living outside. D) Because the place where she lived caught fire.32. A) Because she was disappointed in the college.B) Because she kept moving all the time and couldnt concentrate on studying.C) Because her home was too far away from school and it was inconvenient.D) Because she was not interested in study at all.Passage ThreeQuestions 33-35 are based on the passage you have just heard.33.A) Italian people.B) German people.C) British people.D) French people.34. A) Wash the dishes.B) Have her own meal.C) Make plans for other activities.D) Serve some wine.35. A) OddB) CrazyC) RegularD) RomanticSection CDirections: 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 you have just heard or write down the main points in your own words. Finally, when the passage is read for the third time, you should check what you have written.The Romans built great “aqueducts” to carry fresh water from the mountains to the cities. Many of these aqueducts are still standing today. The Roman (36) _even set up a (37)_ health service. They built the first great public hospitals in Europe, and they paid doctors to look after poor people.When the Roman Empire fell to pieces, these (38) _ methods of treatment (39) _ from most of Europe, for more than a thousand years. People went back to the old ways. They lived in dirty conditions, which helped to cause diseases; and they asked God to cure the (40) _. They shut up (41) _ sick people in prisons. Or they burnt them alive because they were supposed to have (42) _ powers. But the work of the Greek and Roman doctors was not lost.Over a thousand years ago, the Arabs moved into many of the Mediterranean countries. They took big parts of the old (43)_ lands. (44) _ Arab doctors themselves made many new discoveries.(45)_ Slowly, European doctors discovered again the things that the Greeks and Romans had known so long ago. (46) _36. 37. 38. 39. 40. 41. 42. 43. 44. 45. 46. Part Reading Comprehension (Reading in Depth)Section ADirections: In this section, there is a passage with ten blanks. You are required to select one word for each blank from a list of choices given in a word bank following the passage. Read the passage through carefully before making your choices. Each choice in the bank is identified by a letter. Please mark the corresponding letter for each item on Answer Sheet 2 with a single line through the centre. You may not use any of the words in the bank more than once. The process of perceiving other people is rarely translated into cold, objective (47) She was 5 feet 8 inches tall, had fair hair, and wore a colored skirt. More (48) than not, we try to get inside the other person to find out his or her attitudes, emotions, motivations, abilities, ideas, and characters. (49) , we sometimes behave as if we could accomplish this difficult job very quickly-perhaps with a two-send glance. We try to obtain information about others in many ways, Berger suggests several (50) for reducing uncertainties about others: watching, without being noticed, a person interacting with others, particularly with others who are known to you so you can compare the observed persons behavior with the known others behavior; observing a person in a situation where social behavior is relatively unrestricted or where a wide (51) of behavioral responses are called for; deliberately structuring the physical or social environment so as to observe the persons (52) to specific stimuli; asking