大学英语四级考试15选10专项训练

group.Each hut 12 has an inner and an outer door, shutters over the windows, a store of wood 13 up outside, dry chopped wood inside, utensils and cutlery, and above all, a small store of food. All these things must be completely in 14 whenever the hut is left.It makes no 15 if it is only the middle of July. That 16 hut may not be visited again before the winter. A door left open can lead either to snow filling up the hut to the ceiling, or 17 still, wind blowing the roof off. Unfastened shutters leave the windows an easy prey for polar bears 18 for food and the result is again snow in the hut. The ready-chopped wood is also very important.A traveler visiting the hut in the middle of the dark time and perhaps in bad weather, his feet, hands and face bitten by the frost, will have his difficulties doubled if the wood he left has been used up by others and he had nothing with which to19 a fire.Ten or more years ago there were enough hunters to look after most of the huts, but now many buildings have become useless because there is no one to repair them and because of 20A. worseB. peculiarC. laidD. lightE. generallyF. orderG. particularH. conventionsI. carelessness J．difference K. built L. fashionsM. searching N. ordinarily O. resultUnit SevenPassage 2Most of us trade money for entertainment. Movies, concerts and shows are enjoyable but 11 .If you think that you can't have a good time without spending a lot of money, read on. A little resourcefulness and a few minutes ofnewspaper-scanning should give you some pleasant surprises.People may be the most interesting show in a large city. 12 through busy streets and see what everybody else is doing. You will probably see people from all over the world; you will 13 see people of every age, size, and shape, and you'll get a free fashion show, too. Window-shopping is also a 14 sport if the stores are closed.Check the listings in your neighborhood paper. Local colleges or schools often 15 the public to hear an interesting speaker or a good 16 . The film or concert series at the local public library probably won't cost you a penny. Be sure to check commercial advertisements too. A flea market can provide hours of pleasant looking round. Perhaps you can find a free cooking or crafts 17 in a department store.Plan ahead for some activities. It is always more pleasant not to have people in front of you in a museum or at a zoo. You may save some money, too, since these places often 18 aside one or two free 19 days at slow times during the week. Make sure that you are including the indispensable 20 that people travel miles to see. If you feel like taking an interesting walk, find a free walking tour, or plan one yourself.A. expensiveB. WonderC.debateD. admissionE. setF. WanderG.safeH. additionI. valuable J. dispute K.welcome L. confidentlyM. sights N. demonstration O.certainlyUnit EightPassage 2When a person feels low, blue, or down in the clumps, it usually means he has been hurt, disappointed, or saddened by something that causes a confused and listless feeling. There is 11 a type of music called "the blue", a low, mournful, sad sound to 12 these universal human feelings.Depression is another name for this mood. Feeling depressed is a normal and natural 13 to experiences of loss, failure, and undeserved bad luck. Indeed, it has been pointed out that without depression, we would 14 much of the world's great tragic literature, music, and art.In some cases, however, depression becomes something more than just 15 feelings of blues or letdown. A large number of people suffer from what psychiatrists call "depressive illness. " Depressive illness is more 16 and lasts longer than common listless feelings. Sometimes a serious 17 of depression can begin with the loss of a loved one or a change of job. Many times, in very18 cases, there doesn't seem to be any circumstance serious enough to have caused the depression.Some psychiatrists suggest that the key feature in depression is change. The person becomes different from the way before the onset of his depression. He may even become the opposite of his usual self. There are many examples: thebusinessman who becomes a wanderer, the mother who wants to 19 her children and herself. Instead of seeking satisfaction and pleasure, the depressed person 20 it.current 14 for making children compete against their classmates or against the clock produces a two-layer system, in which competitive A types seem in some way better than their B-type fellows. Being 15 keen to win can have dangerous consequences: remember that Pheidippides, the first marathon runner, dropped dead seconds after saying; "cheers, we conquer!"By far the worst form of competition in schools is the extreme 16 on examinations. It is a rare school that allows pupils to 17 on those things they do well. The merits of competition by examination are somewhat 18 , but competition in the certain knowledge of failure is positively harmful.Obviously, it is neither 19 nor desirable that all A youngsters change into B's. The world needs types, and schools have an important duty to try to 20 a child's personality to his possible future employment. It is top management.A. enoughB. fitC. emphasisD. practicalE. innumerableF. concentrateG. adoptH. questionableI. profound J. factor K. too L. substanceM. passion N. emotion O. fixUNIT 12Passage 2As the 11 of life continues to increase, we are fast losing the art of relaxation. Once you are in habit of rushing through life, being on the go from morning till night, it is hard to slow down. But relaxation is essential for a healthy mind and body. Stress is a natural part of everyday life and there is no way to avoid it. In fact, it is not the bad thing it is often 12 to be. A certain amount of stress is 13 to provide motivation and give purpose to life. It is only when the stress gets out of control that it can lead to poor 14 and ill health.The amount of stress a person can 15 depends very much on the individual. Some people are not afraid of stress, and such characters are 16 prime material for managerial responsibilities. Others lose heart at the first signs of 17 difficulties. When exposed to stress, in whatever form, we react both chemically and physically. In fact we make choice between "fight" or "flight" and in more primitive days the choices made the difference between life or death. The crises we meet today are unlikely to be so 18 , but however little the stress, it involves the same response. It is when such a reaction lasts long, through continued 19 to stress, that health becomes endangered. Such serious conditions as high blood pressure and heart disease have established links with stress. Since we cannot 20 stress from our lives(it would be unwise to do so even if we could) , we need to find ways to deal with it.A. cancelB. paceC. extremeD. automaticallyE. removeF. vitalG. performanceH. supposedI. rate J. exposure K. achievement L. unusualM obviously N withstand O harshUnit ThirteenPassage 2What is your favorite color? Do you like yellow, orange, red? If you do, you must be an optimist, a leader, an active person who 11 life, people and excitement. Do you prefer greys and blues? Then you are probably quiet, shy, and you would rather follow than lead. You 12 to be a pessimist. At least, this is what psychologists tell us, and they should know, because they have been seriously studying the meaning of color preference, as well as the effect that colors have on human beings. They tell us, among other 13 , that we do not choose our favorite color as we grow up—we are born with our preference. If you happen to love brown, you did so, as soon as you opened your eyes, or at least as soon as you could see clearly.Colors do 14 our moods—there is no doubt about it. A yellow room makes most people feel more cheerful and more relaxed than a dark green one; and a red dress brings warmth and cheer to the saddest winter day. On the other hand, black is 15 .A black bridge over the Thames River, near London, used to be the 16 of more suicides than any other bridge in the area—until it was repainted green. The number of suicide attempts immediately fell 17 ; perhaps it would have fallen even more if the bridge had been done in pink or baby blue.Light and 18 colors make people not only happier but more active. It isan 19 fact that factory workers work better, harder, and have fewer 20 when their machines are painted orange rather than black or grey.A. brightB. sceneC. whollyD. favorE. factsF. depressingG. accidentsH. interfereI. established J. incidents K. disgusting L. sharplyM. enjoys N. tend O. influenceUnit FourteenPassage 2Women are also underrepresented in the administration and this is because there are so few women 11 professors. In 1985, Regent Beryl Milburn produced a report blasting the University of Texas System administration for not 12 women. The University was rated among the lowest for the system. In a 1587 update, Milburn 13 and praised the progress that was made and called for even more 14One of the positive results from her study was a system-wide program to inform women of available administrative jobs. College of Communication Associate Dean, Patricia Witherspoon, said it is important that woman be 15 when it comes to relocating if they want to 16 in the ranks.Although a woman may face a chilly 17 on campus, many times in order for her to succeed, she must rise above the problems around her and concentrate on her work.Until women make up a greater 18 of the senior positions in the University and all academia, inequalities will exist. "Women need to spend their energies and time doing scholarly activities that are important here at the University. " Spirduso said. "If they do that they will be 19 in this system. If they spend their time in little groups mourning the sexual discrimination that they think exists here, they are 20 wasting valuable study time. "A. fullB. recalledC. improvementD. riseE. encouragingF. flexibleG. recognizedH. idlyI. ratio J. persuading K. movable L. possiblyM. successful N. climate O. percentageUnit FifteenPassage 2In October 1987, the National Board for Professional Teaching Standards began its work to set new standardsof accomplishment for the teaching profession and to improve the 11 of education available to all children in the United States.Teachers are 12 to students and their learning. They must act on the belief that all students can learn. They must recognize 13 differences in their students and adjust their practice 14 . They must know that their mission extends beyond developing the cognitive capacity of their students. They must be 15 with their students' self-concept, with their motivation, and with the development of character.Teachers must know the subjects they teach and how to teach them. They must 16 specialized knowledge of how to convey a subject to students. Teachers are responsible for managing and monitoring student learning. They must call on 17 methods to meet their goals, knowing and being able to 18 a variety of instructional skills. Teachers must think systematically about their practice and learn from experience, seeking the 19 of others and drawing on education research and scholarship to improve their practice.As members of learning communities, teachers contribute to school effectiveness by collaborating with other professionals. They take ___20 ofcommunity resources, cultivating knowledge of their school's community as a powerful resource for learning.A. employB. adviceC. quantityD. committedE. commandF. consultedG. manualH. approximatelyI. concerned J. advantage K. multiple L. accordinglyM. individual N. embrace O. qualityUnit SixteenPassage 2If you are looking for information, library shelves are a good place to start. But if you need up-to-the-minute data or have specialized needs, you may find a computerized database more useful, less expensive, and less time 11 .A database, a file of information on one subject or family of subjects, can be stored and 12 in a computer's memory. The speed of the computer then 13 you to recall any item in this file almost 14The three main types of databases are statistical, bibliographic, and full text. Statistical databases store 15 amounts of numerical data, such as wage and price indexes, census information, foreign 16 rates and bond prices. Bibliographic databases store references to and summaries of articles in periodicals and newspapers. Full-text databases offer the complex texts of such 17 as newspaper, magazine, and journal articles.Thousands of databases exist today, and their numbers are growing. Many companies have their in-house database, which is 18 to employees through computer terminals or microcomputers. In addition, several hundred commercial databases are now available to the 19 , with literally millions of items of information readily obtainable. These databases 20 specific fields, such as law and financial forecasting, or general information, such as sports and weather data.A. exchangeB. publicC. instantlyD. coverE. enablesF. consumingG. remainedH. materialsI. hide J. intensively K. vast L. communicationsM. exhausting N. accessible 0. maintainedUnit SeventeenPassage 2No one knows exactly how many disabled people there are in the world, but 11 suggest the figure is over 450 million. The number of disabled people inIndia 12 is probably more than double the total population of Canada.In the United Kingdom, about one in ten people have some disability. Disability is not just something that happens to other people: as we get older, many of us will become less 13 , hard of hearing or have failing eyesight. Disablement can take many forms and occur at any time of life. Some people are born with disabilities. Many others become disabled as they get older. There are many 14 disabling diseases. The longer time goes on, the worse they become. Some people are disabled in accidents. Many others may have a period of disability in the form of a mental illness. All are affected by people's attitude towards them.Disabled people face many 15 barriers. Next time you go shopping or to work or to visit friends, imagine how you would 16 if you could not get up steps, or on to buses and trains. How would you cope if you could not see where you were going or could not hear the traffic? But there are other barriers; 17 can be even harder to break down and ignorance 18 represents by far the greatest barrier of all. It is almost impossible for the able-bodied to fully appreciate what the severely disabled go through, so it is important to 19 attention to these barriers and show that it is the individual person and their ability, not their disability, which 20A. inevitablyB. evaluationsC. estimatesD. manageE. aloneF. countsG. prejudiceH. physicalI. mobile J. indifferently K. withdraw L. progressiveM. regular N. accounts O. drawUnit EighteenPassage 2Social customs and ways of behaving change. Things which were considered impolite many years ago are now11 . Just a few years ago, it was 12 impolite behavior for a man to smoke on the street. No man who thought of himself as being a gentleman would make a 13 of himself by smoking when a lady was in a room. Customs also differ from country to country. Does a man walk on the left or the right of a woman in your country? Or doesn't it 14 ? What about table manners? Should you use both hands when you are eating? Should you leave one in your lap, or on the table?The Americans and the British not only speak the same language but also 15 a large number of social customs. For example, in both America and England people shake hands when they meet each other for the first time. Also, most Englishmen will open a door for a woman or offer their seat to a woman, and so will most Americans. 16 is important both in England and in America. That is, if a dinner invitation is for 7 o'clock, the dinner guest either arrives 17 to that time or calls up to explain his 18The important thing to remember about social customs is not to do anything that might make other people feel uncomfortable— 19 if they are your guests. There is an old story about a man who gave a formal dinner party. When the food was served, one of the guests started to eat his peas with a knife. The other guests were amused or shocked, but the20 calmly picked up his knifeand began eating in the same way.A. especiallyB. attainableC. closeD. delayE. consideredF. hostG. deliveryH. PreparationI. share J. fool K. specifically L. acceptableM. matter N. Promptness 0. careUnit NineteenPassage 2The economy of the United States after 1952 was the economy of a well-fed, almost fully employed people. Despite 11 alarms, the country escaped any postwar depression and lived in a 12 of boom. An economic survey of the year 1955, a typical year of the 1950's, may be typical as 13 the rapid economic growth of the decade. The national output was 14 at 10 percent above that of 1954(1955 output was estimated at 392 billion dollars). The production of manufactures was about 40percent more than it had 15 in the years immediately following World War I . The country's business spent about 30 billion dollars for new factories and machinery. National income 16 for spending was almost a third greater than it had been in 1950. Consumers spent about 256 billion dollars; that is about 700 million dollars a day, or about twenty-five million dollars every hour, all round the 17 . Sixty-five million people held jobs and only a little more than two million wanted jobs but could not find them. Only agriculture 18 that it was not sharing in the boom. To some observers this was a sad reflection of the mid-1920's. As farmers' share of their products 19 , marketing costs rose. But there were, among the observers of the national economy, a few who were not as confident as the majority. Those few seemed to fear that the boom could not last long and would20 lead to the opposite—depression.A. eventuallyB. averagedC. graduallyD. stateE. valuedF. formG. declinedH. occasionalI. casual J. argued K. descended L. complainedM. clock N. available O. illustratingUnit TwentyPassage 2Growth of trade will depend greatly on availability of energy sources. There may still be a trillion barrels of recoverable oil in the Middle East. But the oil crisis of 1974 has 11 to renewed interest in coal and to a search for12 sources of energy. Solar, geothermal, and nuclear energy will play a large role in the years to come.Solar energy is available in 13 forms. Buildings can be heated and cooled by direct use of solar radiation, crops and trees, which are the most efficient converters of sunlight into energy, can be grown for their energy potential, wastes can be burned as 14 , sunlight can be converted into DC (direct current) electricity, electric power can be 15 from the sun-warmed surface waters of the ocean, and lastly, solar radiation can be converted into heat that will drive electric power generators. Serious problems still remain as to 16 and storage of solar energy.Geothermal energy is the energy contained within the earth. Heat is abundantly available deep in the earth's core and is constantly being produced. However, this heat is usually located at too deep a level for 17 exploitation. In short, very little is known on the use of geothermal energy, and it has 18 been exploited.Nuclear energy is produced in nuclear power plants. At these plants atoms of uranium are split, thus 19masses of energy. Another source of energyunder development is the nuclear fusion of certain atoms of hydrogen. This could eventually 20 natural gas as a source of energy.A. rarelyB. transformationC. fuelD. replaceE. ledF. alternativeG. commercialH. brieflyI. derived J. various K. relieving L. releasingM. transportation N. financial O. describedUNIT 21Like most parents, geologist Brain Atwater worries about his daughter's safety. But these days, he has an unusual concern; The public school she 11 in Seattle has unreinforced brick walls, a 12 being easy to collapse during earthquakes. The same 13 of walls crushed hundreds of thousands of people during the 1976 Tangshan quake in China.A decade ago, Atwater would have paid little notice to schoolroom walls. But over the last several years, he and other scientists have found 14 signs that the Pacific Northwest has experienced giant quakes in the distant past and that the area may be headed for a destructive shock in the near future.At a meeting of the American Geophysical Union in December, researchers discussed the 15 uncovered evidence of quake potential in the Pacific Northwest. While some remain unconvinced that huge earthquakes—with magnitudes of 8 or higher—do indeed 16 this region, a growing number consider such shocks a serious possibility.What's worrisome, they say, is that northwestern cities such as Portland, Seattle and Vancouver have not prepared for earthquakes of this magnitude, which could shake the region's 17 centers with enough force to make the recent San Francisco area damage seem 18 in comparison."I think it's quite true to say that nothing has really been designed with one of these earthquakes in mind," says seismologist Paul Somerville of Woodward. At the meeting, Somerville and his colleagues 19 estimates of the degree of shaking. Portland and Seattle would suffer during such a 20 earthquake.A. massiveB. recentlyC. constructionD. displayedE. relativelyF. attendsG. typeH. strikemosquito is only a matter of inches from its 15 the warmth and moisture given off by the victim is the final clue.The researchers then * 16 how repellents interfere with its three-stage attack. They found repellents act more subtly than by just giving off a nasty smell. A Canadian researcher says that repellents appear to 17 mosquitoes first when it is following the carbon dioxide and second during the final approach, where the warmth and moisture are the insect's 18 . Air pervaded by one of the many chemical repellents stops the mosquito reacting to the victim's carbon dioxide, and the repellent seems to affect the tiny hairs with which the insect senses moisture in the air. The sensors are blocked so that the 19 does not know whether it is flying through a moist current, orthe sensors are made to send the 20 signals.A. examinedB. animalC. wrongD. insectE. biteF. UnfortunatelyG. inventingH. distinctI. prey J. guide K. checked L. definiteM. Unnecessarily N. confuse O. discoveringUnit Twenty-FivePassage 2Climate, more than any other single factor, 11 the distribution of life on Earth. Climatic boundaries establish the limits within which organisms can survive. Plants, even more than animals, must be 12 adapted to climate in order to survive. They cannot move about or take shelter but must be equipped to 13 whatever weather conditions are likely to occur. In the harsh conditions of the far north of the earth, for example, low growing mosses, lichens, and a few flowering plants all hold to the ground for shelter from icy winds.Animals, despite their 14 to move about and find shelter, are just as much influenced by climate as plants are. Creatures such as the camel and the penguin are so highly specialized that they have an 15 limited distribution. Others, such as bears, are flexible enough to adapt to a 16 range of climates.. Ocean-dwelling organisms are just as sensitive to climatic changes—in this case temperature and salinity—as land animals. Reef corals can survive only in clear warm seawater. Certain foraminaters are so sensitive to changes in their 17 that their presence can be taken as an 18 of sea temperature. Human beings are among the 19 specialized of all animals and can live almost anywhere. Their clothes and their homes20 as a sort of "miniature climate" that can be taken with them everywhere.A. leastB. determines c. ability D. urgentlyE. broadF. behaveG. worstH. indexI. endure J. extremely K. entertain L. wellM. neighborhood N. act O. environmentUnit Twenty-SixPassage 2I have never attended a large company's board meeting in my life, but I feel certain that the discussion often takes the following lines. The 11 of producing a new—for example—toothpaste would make 8 Op the decent price for it, so we will market it at £l. 20. It is not a bad toothpaste (not specially good either, but not bad) , and as people like to try new things it will sell well to start with; but the 12 of novelty soon fades, so sales will 13 . When that starts to happen we will reduce the price to £l. 15. And we will turn it into a bargain by printing 5p OFF all over it, whereupon people will rush to buy it even though it still costs about forty-three percent more than its 14 price.Sometimes it is not 5p OFF but lp OFF. What a shame to advertise lp OFF your soap or washing powder or dog food or whatever. Even the poorest old-age pensioner ought to regard this as an insult, but he doesn't. A bargain must not be 15 To be offered a "gift" of one penny is like being invited to dinner and offered one single pea (tastily cooked), and nothing else. Even if it represented a 16 reduction it would be an insult. Still, people say, one has to have washing powder (or whatever) and one might as well buy it a penny cheaper. When I was a boy in Hungary a man was 17 of murdering someone for the sake of one pengo, the equivalent of a shilling, and pleaded 18 The judge shouted 19 : "To kill a man for a shilling! What can you say in your 20 ?" The murderer replied: "A shilling here. . . a shilling there. . . " And that's what today's shopper says, too: "A penny here... a penny there. . . "A. missedB. defenseC. realD. costE. anxiouslyF. attractionG. fairH. expenseI. fall J. angrily K. dismissed L. accusedM. guilty N. faulty O. securityUnit Twenty-SevenPassage 2Sugar is so much a part of our modern life that we only really think about it when, for some 11 , we cannot obtain it. It hasbeen known to man for at least 3,000 years, but has 12 into common use only in 13 times. Until quite recently it was considered as a medicine and as a luxury for the very rich only.Sugar is, then, 14 to our civilization. But what 15 is it? Of course, most of us recognize sugar immediately as the sweet material which we put in coffee or cakes. This common form of sugar is derived from two plants: the sugar cane (a type of grass which grows to a height of twenty feet) and the sugar beet (which grows under ground). But there are in fact many types of sugar, and the chemist recognizes hundreds of different 16 , each coming from a different source.About 90% of the sugar is produced as food. Only 10% is used in industry for 17 other than food production. Yet sugar has great possibilities for use as the basis of chemicals. It can even be used for making plastics. In the future these potential uses will certainly be developed more than in the past.There are many reasons why we should 18 the production of sugar. Most important is that it is one of the most highly concentrated of energy foods.Thus sugar cane and beet produce an average of 7,000,000 calories per acre. In this way they have the advantage over potatoes which give only 4, 000, 000, while the 19 for wheat and beans is 2 ,000,000 each. So three acres of land growing wheat, beans and potatoes give only 20 more energy than one acreof sugar.A. slightlyB. intentionC. reasonD. modernE. stronglyF. figureG. comeH. significantI. exactly J. increase K. proposals L. turnM. purposes N. varieties O. seriousUnit Twenty-EightPassage 2The birth of computers has brought with it a new set of opportunities for mischief and crime. Today, computers are easy to come by and many people know how computer technology 11 . More importantly, the growing use of computer networks can multiply the violation of security, making large numbers of people more vulnerable than would be the case if they were using 12 , stand-alone computers.What's more, computer experts agree that—despite recent widespread publicity-computer viruses are 13 one of the many computer security problems facing the nation.The U. S. Defense Advanced Research Project Agency has requested that the Research Council's Science and Technology Board 14 the security problems posed by computer technology, see what 15 may already exist, review research efforts 16 at avoiding security problems in the future, and evaluate existing policies 17 to computer security. The study committee will examine the 18 of security for a broad spectrum of users, including the business, national security, and academic communities, as well as the 19 public.David. Clark, senior research scientist, Laboratory for Computer Science, Massachusetts Institute of Technology, will chair the 20 of experts inelectronic security, net-work security, computer law, software engineering ? and operating systems. The committee will also include computer users from the defense and banking industries.A. onlyB. worksC. solutionsD. generalE. issueF. fundamentallyG. universalH. assessI. aimed J. single K. committee L. generatesM. relevant N. question O. communityUnit Twenty-NinePassage 2Leonardo da Vinci was the first man to suggest that growing trees add a new ring in their trunks each year. The11 in these rings relates to the physical conditions which the tree experiences. Thus, trees grown in a 12 area and time each develop a pattern or configuration of their rings.This 13 was of little significance until Andrew E. Douglas began to study tree rings in Arizona in 1900. Using a technique called cross dating, he was able to employ tree rings to the study of archaeological sites and date the ruins with 14 . Some were as old as 6700 B. C. ! This study of tree rings is called dendrochronology.In time the cross dating was 15 by a carbon 14 process. This approach measured the amount of carbon 14 radiating from a piece of wood and 16 to determine the age of that wood. Further use of the carbon 14 technique has shown that the radiation process is more complex and less 17 than had been at first thought.The most 18 aspect of tree ring research is now called dendroclimatology. This 19 of the reconstruction of climates and climatic cycles and events from the evidence found in the tree rings. From this it is hoped that a 20 of drought cycles can be determined in the American Southwest. Such information。