研究生类
公务员类
工程类
语言类
金融会计类
计算机类
医学类
研究生类
专业技术资格
职业技能资格
学历类
党建思政类
博士研究生考试
公共课
专业课
全国联考
同等学历申硕考试
博士研究生考试
考博英语
考博英语
单选题{{B}}Passage Two{{/B}} The two claws of the mature American lobster are decidedly different from each other. The crusher claw is short and stout; the cutter claw is long and slender. Such bilateral asymmetry, in which the right side of the body is, in all other respects, a mirror image of the left side, is not unlike handedness in humans. But where the majority of humans are right-handed, in lobsters the crusher claw appears with equal probability on either the right side or left side of the body. Bilateral asymmetry of the claws comes about gradually. In the juvenile fourth and fifth stages of development, the paired claws are symmetrical and cutterlike. Asymmetry begins to appear in the juvenile sixth stage of development, and the paired claws further diverge toward well-defined cutter and crusher claws during succeeding stages. An intriguing aspect of this development was discovered by Victor Emmel. He found that if one of the paired claws is removed during the fourth or fifth stage, the intact claw invariably becomes a crusher, while the regenerated claw becomes a cutter. Removal of a claw during a later juvenile stage or during adulthood, when asymmetry is present, does not alter the asymmetry; the intact and regenerate claws retain their original structures. These observations indicate that the conditions that trigger differentiation must operate in a random manner when the paired claws are intact but in a nonrandom manner when one of the claws is lost. One possible explanation is that differential use of the claws determines their asymmetry. Perhaps the claw that is used more becomes the crusher. This would explain why, when one of the claws is missing during the fourth or fifth stage, the intact claw always becomes a crusher. With two intact claws, initial use of one claw might prompt the animal to use it more than the other throughout the juvenile fourth and fifth stages, causing it to become a crusher. To test this hypothesis, researchers raised lobsters in the juvenile fourth and fifth stages of development in a laboratory environment in which the lobsters could manipulate oyster chips. (Not coincidentally, at this stage of development lobsters typically change from a habitat where they drift passively, to the ocean floor where they have the opportunity to be more active by borrowing in the substrate.) Under these conditions, the lobsters developed asymmetric claws, half with cutter claws on the left, and half with crusher claws on the right. In contrast, when juvenile lobsters were reared in a smooth tank without the oyster chips, the majority developed two cutter claws. This unusual configuration of symmetrical cutter claws did not change when the lobsters were subsequently placed in a manipulatable environment or when they lost and regenerated one or both claws.
进入题库练习
单选题Many people invest in the stock market hoping to find the next Microsoft and Dell. However, I know (21) personal experience how difficult this really is. For more than a year, I was (22) hundreds and sometimes thousands of dollars a day in investing in the market. It seemed so easy, I dreamed of (23) my job at the end of the year, of buying a small apartment in Paris, of traveling around the world. But these dreams (24) to a sudden and dramatic end when a stock I (25) , Texas cellular phone wholesaler, fell by more than 75 percent (26) a one-year period. On the (27) day, it plunged by more than $15 a share. There was a rumor that the company was (28) sales figures. That was when I learned how quickly Wall Street (29) companies that, in one way or another, misrepresent the (30) . In a (31) , I sold all my stocks in the company, paying (32) margin debt with cash advances from my (33) card. Because I owned so many shares, I (34) a small fortune, half of it from money I borrowed from the brokerage company. One month, I am a (35) , the next, a loser. This one big loss was my first lesson in the market. My father was a stockbroker, as was my grandfather (36) him. (In fact, he founded one of Chicago's earliest brokerage firms. )But like so many things in life, we don't learn anything until we (37) it for ourselves. The only way to really understand the inner (38) of the stock market is to invest your own hard-earned money. When all your stocks are doing (39) and you feel like a winner, you learn very little. It's when all are losing and everyone is questioning your stock-picking (40) that you find out if you have what it takes to invest in the market.
进入题库练习
单选题The report managed to get an ______ interview with the Prime Minister.
进入题库练习
单选题{{B}}Passage 2{{/B}} Montaigne's hold on his readers arises from many causes. There is his frank and curious self-delineation. That interests, because it is the revelation of a very peculiar nature. Then there is the positive value of separate thoughts imbedded in iris strange whimsicality and humor. Lastly, there is the perennial charm of style, which is never a separate quality, but rather the amalgam and issue of all the mental and moral qualities in a man's possession, and which bears the same relation to these that light bears to the mingled elements that make up the orb of the sun. And style, after all, rather than thought, is the immortal thing in literature. In literature, the charm of style is indefinable, yet all subduing, just as fine manners are in social life. In reality, it is not of so much consequence what you say, as how you say it. Memorable sentences are memorable on account of some irradiating word. "But Shadwell never deviates into sense, for instance." Young Roscius, in his provincial barn, will repeat you the great soliloquy of Hamlet, and although every word may be given with tolerable correctness, you find it just as commonplace as himself. The great actor speaks it, and you "read Shakespeare as by a flash of lightning". And it is in Montaigne's style, in the strange freaks and turnings of his thought, his constant surprises, his curious alternations of humor and melancholy, his careless, familiar form of address, and the grace with which everything is done, that his charm lies, and which makes the hundredth perusal of him as pleasant as the first.
进入题库练习
单选题After graduation, he was ______ to a teaching post. But a year later, he resigned from the job and plunged himself into business.
进入题库练习
单选题They were tired, but not any less enthusiastic ______ that account.(2003年复旦大学考博试题)
进入题库练习
单选题As far as she is concerned, one piece of music is very much like ______
进入题库练习
单选题The school committee naturally hope that their choice of play will be ______ with the school and parents.
进入题库练习
单选题The period in Europe from the end of the World War II has seen a spectacular growth in the number of cars, similar to ______ in America during the 1920s and 1930s. A. what would take place B. that which took place C. which had taken place D. that were taking place
进入题库练习
单选题It is all very well to blame traffic jams, the cost of petrol and the quick pace of modern life, but manners on the roads are becoming horrible. Everybody knows that the nicest men become monsters behind the wheel. It is all very well, again, to have a tiger in the tank, but to have one in the driver's seat is another matter altogether. You might tolerate the odd road-hog, the rude and inconsiderate driver, but nowadays the well-mannered motorist is the exception to the rule.(Perhaps the situation calls for a "Be Kind to Other Drivers" campaign, otherwise it may get completely out of hand.) Road politeness is not only good manners, but good sense too. It takes the most cool-headed and good-tempered of drivers to resist the temptation to revenge when subjected to uncivilized behavior. On the other hand, a little politeness goes a long way towards relieving the tensions of motoring. A friendly nod or a wave of acknowledgment in response to an act of politeness helps to create an atmosphere of goodwill and tolerance so necessary in modern traffic conditions. But such acknowledgments of politeness are all too rare today. Many drivers nowadays don't even seem able to recognize politeness when they see it. However, misplaced politeness can also be dangerous. Typical examples are the driver who brakes violently to allow a car to emerge from a side street at some hazard to following traffic, when a few seconds later the road would be clear anyway; or the man who waves a child across a zebra crossing into the path of oncoming vehicles that may be unable to stop in time. The same goes for encouraging old ladies to cross the road wherever and whenever they care to. It always amazes me that the highways are not covered with the dead bodies of these grannies. A veteran driver, whose manners are faultless, told me it would help if motorists learnt to filter correctly into traffic streams one at a time without causing the total blockages that give rise to bad temper. Unfortunately, modern motorists can't even learn to drive, let alone master the subtler aspects of roadsmanship. Years ago the experts warned us that the car ownership explosion would demand a lot more give-and-take from all road users. It is high time for all of us to take this message to heart.
进入题库练习
单选题Recognizing the shortage of time available to spend with their children, working mothers sometimes take ______ in the concept of "quality time".
进入题库练习
单选题In protest, blacks and ______ whites sat at the counters of these restaurants and refused to move until they were sewed. A.sensible B.indifferent C.influential D.sympathetic
进入题库练习
单选题Because a circle has no beginning or end, the wedding ring is a symbol of______ love.(2002年厦门大学考博试题)
进入题库练习
单选题It is surprising that such an innocent-looking man should have____such a crime.
进入题库练习
单选题Failure to follow the club rules ______ him from the volleyball team. A. disfavoured B. dispelled C. disqualified D. dismissed
进入题库练习
单选题Personality is to a large extent inherent—A-type parents usually bring about A-type offspring. But the environment must also have a profound effect, since if competition is important to the parents, it is likely to become a major factor in the lives of their children. One place where children soak up A-characteristics is school, which is, by its very nature, a highly competitive institution. Too many schools adopt "the win at all costs" moral standard and measure their success by sporting achievements. The current passion 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 too keen to win can have dangerous consequences: remember that Pheidippides, the first marathon runner, dropped dead seconds after saying: "Rejoice, we conquer!" By far the worst form of competition in schools is the disproportionate emphasis on examinations. It is a rare school that allows pupils to concentrate on those things they do well. The merits of competition by examination are somewhat questionable, but competition in the certain knowledge of failure is positively harmful. Obviously, it is neither practical nor desirable that all A-youngsters change into B's. The world needs A-types, and schools have an important duty to try to fit a child's personality to his possible future employment. It is top management. If the preoccupation of schools with academic work was lessened, more time might be spent teaching children surer values. Perhaps selection for the caring professions, especially medicine could be made less by good grades in chemistry and more by such considerations as sensitivity and sympathy. It is surely a mistake to choose our doctors exclusively from A-type stock. B's are important and should be encouraged.
进入题库练习
单选题The baby seems content; he must have ______ his new nursemaid.
进入题库练习
单选题Questions 24—26 are based on a report about a book, "Paris: Capital of the World." You now have 15 seconds to read Questions 24—26.
进入题库练习
单选题Mass transportation revised the social and economic fabric of the American city in three fundamental ways. It catalyzed physical expansion, it sorted out people and land uses, and it accelerated the inherent instability of urban life. By opening vast areas of unoccupied land for residential expansion, the omnibuses, horse railways, commuter trains, and electric trolleys pulled settled regions outward two to four times more distant from city centers than they were inthe premodern era. In 1850, for example, the borders of Boston lay scarcely two miles from the old business district. By the turn of the century the radius extended ten miles. Now those who could afford it could live far removed from the old city center and still commute there for work, shopping, and entertainment. The new accessibility of land around the periphery of almost every major city sparked an explosion of real estate development and pulled what we now know as urban sprawl. Between 1890 and 1920, for example, some 250000 new residential lots were recorded within the borders of Chicago; most of them located in outlying areas. Over the same period, another 550000 were plotted outside the city limits but within the metropolitan area. Anxious to take advantage of the possibilities of commuting, real estate developers added 800000 potential building sits to the Chicago region in just thirty years lots that could have housed five to six million people.
进入题库练习
单选题He got home two hours late and said he had been ______ in the office by business. A. detached B. detained C. obstructed D. obsessed
进入题库练习