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单选题Little boys seem to enjoy______ train sets more than little girls.(2003年中国社会科学院考博试题)
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单选题The current financial crisis ______ a holistic, global approach to deal with all issues. A. cries out for B. gets hold of C. boils down to D. goes in for
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单选题Since the dawn of human ingenuity, people have devised ever more cunning tools to cope with work that is dangerous, boring, burdensome, or just plain nasty. That compulsion has resulted in robotics—the science of conferring various human capabilities on machines. And ff scientists have yet to create the mechanical version of science fiction, they have begun to come close. As a result, the modern world is increasingly populated by intelligent gizmos whose presence we barely notice but whose universal existence has removed much human labor. Our factories hum to the rhythm of robot assembly arms. Our banking is done at automated teller terminals that thank us with mechanical politeness for the transaction. Our subway trains are controlled by tireless robot-drivers. And thanks to the continual miniaturization of electronics and micro-mechanics, there are already robot systems that can perform some kinds of brain and bone surgery with submillimeter accuracy—far greater precision than highly skilled physicians can achieve with their hands alone. But if robots are to reach the next stage of laborsaving utility, they will have to operate with less human supervision and be able to make at least a few decisions for themselves—goals that pose a real challenge. "While we know how to tell a robot to handle a specific error," says Dave Lavery, manager of a robotics program at NASA, "we can't yet give a robot enough 'common sense' to reliably interact with a dynamic world." Indeed the quest for true artificial intelligence has produced very mixed results. Despite a spell of initial optimism in the 1960s and 1970s when it appeared that transistor circuits and microprocessors might be able to copy the action of the human brain by the year 2010, researchers lately have begun to extend that forecast by decades if not centuries. What they found, in attempting to model thought, is that the human brain's roughly one hundred billion nerve cells are much more talented—and human perception far more complicated—than previously imagined. They have built robots that can recognize the error of a machine panel by a fraction of a millimeter in a controlled factory environment. But the human mind can glimpse a rapidly changing scene and immediately disregard the 98 percent that is irrelevant, instantaneously focusing on the monkey at the side of a winding forest road or the single suspicious face in a big crowd. The most advanced computer systems on the earth can't approach that kind of ability, and neuroscientists still don't know quite how we do it.
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单选题The 9/11 Attacks were a series of four coordinated suicide attacks upon the United States in the New York City and the Washington D.C.areas in September of______.
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单选题______is the collective term for the type of morpheme that can be used only when added to another morpheme.
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单选题
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单选题The American economic system is organized around a basically private-enterprise, market oriented economy in which consumers largely determine what shall be produced by spending their money in the marketplace for those goods and services that they want most. Private businessmen, striving to make their profits, produce these goods and services in competition with other businessmen: and the profit motive, operating under competitive pressures, largely determines how these goods and services are produced. Thus, in the American economic system it is the demand of individual consumers, coupled with the desire of businessmen to maximize profits and the desire of individuals to maximize their incomes, that together determine what shall be produced and how resources are used to produce it. An important factor in a market-oriented economy is the mechanism by which consumer demands can be expressed and responded to by producers. In the American economy, this mechanism is provided by a price system, a process in which prices rise and fall in response to relative demands of consumers and supplies offered by seller-producers. If the product is in short supply relative to the demand, the price will be a bit up and some consumers will be eliminated from the market. If, on the other hand, producing more of a commodity results in reducing its cost, this will tend to increase the supply offered by seller-producers, which in turn will lower the price and permit more consumers to buy the product. Thus, price is the regulating mechanism in the American economic system. The important factor in a private-oriented economy is that individuals are allowed to own productive resources (private property), and they are permitted to hire labor, gain control over natural resources, and produce goods and services for sale at a profit. In the American economy, the concept of private property embraces not only the ownership of productive resources but also certain rights, including the right to determine the price of a product or to make a free contract with another private individual.
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单选题It can be concluded from this article that the attraction of the sun is ______.
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单选题The______of College English Tests is to help students learn English better, isn't it?
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单选题{{B}}Questions 11-15 are based on the following passage:{{/B}} Real policemen hardly recognize any resemblance(类同之处)between their lives and what they see on TV—if they ever get home in time. There are similarities, of course, but the cops (警官) don't think much of them. The first difference is that a policeman's real life revolves round the law. Most of his training is in criminal law. He has to know exactly what actions are crimes and what evidence can be used to prove them in court. He has to know nearly as much law as a professional lawyer, and what is more, he has to apply it on his feet, in the dark and rain, running down an alley after someone he wants to talk to. Little of his time is spent in chatting to scanty-clad ( 穿衣不多的 ) ladies or in dramatic confrontations with desperate criminals. He will spend most of his working life typing millions of words on thousands of forms about hundreds of sad, unimportant people who are guilt or not—of stupid, petty crimes.
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单选题Ethics was generally considered to be
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单选题The geology of the Earth's surface is dominated by the particular properties of water. Present on Earth in solid, liquid, and gaseous states, water is exceptionally reactive. It dissolves, transports, and precipitates many chemical compounds and is constantly modifying the face of the Earth. Evaporated from the oceans, water vapor forms clouds, some of which are transported by wind over the continents. Condensation from the clouds provides the essential agent of continental erosion; rain. Precipitated onto the ground, the water trickles down to form brooks, streams, and rivers, constituting what is called the hydrographic network. This immense polarized network channels the water toward a single receptacle; an ocean. Gravity dominates this entire step in the cycle because water tends to minimize its potential energy by running from high altitudes toward the reference point that is sea level. The rate at which a molecule of water passes through the cycle is not random but is a measure of the relative size of the various reservoirs. If we define residence time as the average time for a water molecule to pass through one of the three reservoirs — atmosphere, continent, and ocean — we see that the times are very different. A water molecule stays, on an average, eleven days in the atmosphere, one hundred years on a continent and forty thousand years in the ocean. This last figure shows the importance of the ocean as the principal reservoir of the hydrosphere but also the rapidity of water transport on the continents. A vast chemical separation process takes places during the flow of water over the continents. Soluble ions such as calcium, sodium, potassium, and some magnesium are dissolved and transported. Insoluble ions such as aluminum, iron, and silicon stay where they are and form the thin, fertile skin of soil on which vegetation can grow. Sometimes soils are destroyed and transported mechanically during flooding. The erosion of the continents thus results from two closely linked and interdependent processes, chemical erosion and mechanical erosion. Their respective interactions and efficiency depend on different factors.
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单选题With a lot of difficult problems ______, the newly-elected president is having a hard time.
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单选题The bell is ringing ______ the lesson is over.A. butB. orC. andD. yet
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单选题After comparing "They stopped at the end of the corridor." with "At the end of the corridor, they stopped", you may find some difference in meaning, and the difference can be interpreted in terms of collocative meaning. (北二外2006研)
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单选题The engineers are going through with their highway project, ______ the expenses have risen. A. even though B. just because C. now that D. as though
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单选题
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单选题Mr. Green is considering ______ the job because he needs to get additional experience.
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单选题The child was ______ for getting his shoes and socks wet. A. stopped B. blame C. accused D. complained
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单选题{{B}}Passage 2{{/B}} When it comes to the slowing economy, Ellen Spero isn't biting her nails just yet. But the 47-year-old manicurist isn't cutting, filling or polishing as many nails as she'd like to, either. Most of her clients spend $12 to $ 50 weekly, but last month two longtime customers suddenly stopped showing up. Spero blames the softening economy. "I'm a good economic indicator," She says. "I provide a service that people can do without when they're concerned about saving some dollars. " So Spero is downscaling, shopping at middle-brow Dillard's department store near her suburban Cleveland home, instead of Neiman Marcus. "I don't know if other clients are going to abandon me, too," she says. Even before Alan Greenspan's admission that America's red-hot economy is cooling, lots of working folks had already seen signs of the slowdown themselves. From car dealerships to Gap outlets, sales have been lagging for months as shoppers temper their spending. For retailers, who last year took in 24 percent of their revenue between Thanksgiving and Christmas, the cautious approach is coming at a crucial time. Already, experts say, holiday sales are off 7 percent from last year's pace. But don't sound any alarms just yet. Consumers seem only mildly concerned, not panicked, and many say they remain optimistic about the economy's long-term prospects, even as they do some modest belt-tightening. Consumers say they're not in despair because, despite the dreadful headlines, their own fortunes still feel pretty good. Home prices are holding steady in most regions. In Manhattan, "there's a new gold rush happening in the $4 million to $10 million range, predominantly fed by Wall Street bonuses," says broker Barbara Corcoran. In San Francisco, prices are still rising even as frenzied overbidding quiets. "Instead of 20 to 30 offers, now maybe you only get two or three," says John Tealdi, a Bay Area real-estate broker. And most folks still feel pretty comfortable about their ability to find and keep a job. Many folks see silver linings to this slowdown. Potential home buyers would cheer for lower interest rates. Employers wouldn't mind a little fewer bubbles in the job market. Many consumers seem to have been influenced by stock-market swings, which investors now view as a necessary ingredient to a sustained boom. Diners might see an upside, too. Getting a table at Manhattan's hot new Alain Ducasse restaurant used to be impossible. Not anymore. For that, Greenspan & Co. may still be worth toasting.
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