单选题If it is left ______, this fast-spreading disease is likely to affect millions of Asian and African children, including more and more injured grown-ups. A. unchecked B. uncontrolled C. transmitted D. contaminated

单选题Mr. Smith gradually ______ a knowledge of the subject.

单选题The ______ action of the policemen saved the people in the house from being burnt. A. supreme B. significant C. prompt D. vital

单选题{{B}}Passage One{{/B}} Oceanography has been defined as "the application of all sciences to the study of the sea". Before the nineteen century, scientists with an interest in the sea were few and far between. Certainly Newton considered some theoretical aspects of it in his writings, but he was reluctant to go to sea to further his work. For most people the sea was remote, and with the exception of early intercontinental travelers or others who earned a living from the sea, there was little reason to ask many questions about it, let alone to ask what lay beneath the surface. The first time that question "What is at the bottom of the oceans?" had to be answered with any commercial consequence was when the laying of a telegraph cable from Europe to America was proposed. The engineers had to know the depth profile of the route to estimate the length of cable that had to be manufactured. It was to Maury of the U.S. Navy that the Atlantic Telegraph Company turned, in 1853, for information on this matter. In the 1840s, Maury had been responsible for encouraging voyages during which soundings were taken to investigate the depths of the North Atlantic and Pacific Oceans. Later, some of his findings aroused much popular interest in his book The Physical Geography of the Sea. The cable was laid, but not until 1866 was the connection made permanent and reliable. At the early attempts, the cable failed and when it was taken out for repairs it was found to be covered in living growths, a fact which defied contemporary scientific opinion that there was no life in the deeper parts of the sea. Within a few years oceanography was under way. In 1872 Thomson led a scientific expedition, which lasted for four years and brought home thousands of samples from the sea. Their classification and analysis occupied scientists for years and led to a five-volume report, the last volume being published in 1895.

单选题The greatest advance that Librie has is that

单选题Science is a dominant theme in our culture. Since it touches almost every facet of our life, educated People need at least some acquaintance with its structure and operation. They should also have an understanding of the subculture in which scientists live and the kinds of people they are. An understanding of general characteristics of science as well as specific scientific concepts is easier to attain if one knows something about the things that excite and frustrate the scientist. This book is written for the intelligent student or lay person whose acquaintance with science is superficial; for the person who has been presented with science as a musty store-house of dried facts; for the person who has been presented with science as the production of gadgets; and for the person who views the scientists as some sort of magician. The book can be used to supplement a course in any science, to accompany any course that attempts to give an understanding of the modern world, or, independently of any course--simply to provide a better understanding of science. We hope this book will lead readers to a broader perspective on scientific attitudes and a more realistic view of what science is, who scientists are, and what they do. It will give them an awareness and understanding of the relationship between science and our culture and an appreciation of the roles science may play in our culture. In addition, readers may learn to appreciate the relationship between scientific views and some of the values and philosophies that are pervasive in our culture. We have tried to present in this book an accurate and up-to-date picture of the scientific community and the people who populated it. That population has in recent years come to comprise more and more women. This increasing role of women in the scientific subculture is not an unique incident but, rather, part of the trend evident in all segments of society as more women enter traditionally male-dominated fields and make significant contributions. In discussing these changes and contributions, however, we are faced with a language that is implicitly sexist, one that uses male nouns or pronouns in referring to unspecified individuals. To offset this built-in bias, we have adopted the policy of using plural nouns and pronouns whenever possible and, when absolutely' necessary, alternating he and she. This policy is far from being ideal, but it is at least an acknowledgment of the inadequacy of our language in treating half of the human race equally. We have also tried to make the book entertaining as well as informative. Our approach is usually informal. We feel, as do many other scientists, that we shouldn't take ourselves too seriously. As the reader may observe, we see science as a delightful pastime rather than as a grim and dreary way to earn a living.

单选题The percentage of immigrants (including those unlawfully present) in the United States has been creeping upward for years. At 12.6 percent, it is now higher than at any point since the mid-1920s. We are not about to go back to the days when Congress openly worried about inferior races polluting America's bloodstream. But once again we are wondering whether we have too many of the wrong sort of newcomers. Their loudest critics argue that the new wave of immigrants cannot, and indeed do not want to, fit in as previous generations did. We now know that these racist views were wrong. In time, Italians, Romanians and members of other so-called inferior races became exemplary Americans and contributed greatly, in ways too numerous to detail, to the building of this magnificent nation. There is no reason why these new immigrants should not have the same success. Although children of Mexican immigrants do better, in terms of educational and professional attainment, than their parents, UCLA sociologist Edward Telles has found that the gains don't continue. Indeed, the fourth generation is marginally worse off than the third. James Jackson, of the University of Michigan, has found a similar trend among black Caribbean immigrants, Telles fears that Mexican-Americans may be fated to follow in the footsteps of American blacks—that large parts of the community may become mired (陷入) in a seemingly permanent state of poverty and underachievement. Like African-Americans, Mexican-Americans are increasingly relegated to(降入) segregated(隔离), substandard schools, and their dropout rate is the highest for any ethnic group in the country. We have learned much about the foolish idea of excluding people on the presumption of the ethnic/racial inferiority. But what we have not yet learned is how to make the process of Americanization work for all. I am not talking about requiring people to learn English or to adopt American ways; those things happen pretty much on their own. But as arguments about immigration heat up the campaign trail, we also ought to ask some broader questions about assimilation (同化), about how to ensure that people, once outsiders, don't forever remain marginalized within these shores. That is a much larger question than what should happen with undocumented workers, or how best to secure the border, and it is one that affects not only newcomers but groups that have been here for generations. It will have more impact on our future than where we decide to set the admissions bar for the latest wave of would-be Americans. And it would be nice if we finally got the answer right.

单选题The illness had left her feeling tired and ______.A. strongB. happyC. weakD. hungry

单选题Inflation has surged in recent months due to double-digit spike in sensitive food prices blamed on shortages of pork and other basic goods. A. sharp rise C. dramatic drop B. regular increase D. anticipated decrease

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 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 bid 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-enterprise 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.

单选题The company will ______to its agreement, no matter how costly the process may be.(2002年中国人民大学考博试题)

单选题______ for several times, Bill made up his mind not to play computer games at night any more. A. To be scolded B. To have been scolded C. Being scolded D. Having been scolded

单选题{{B}}Text 4{{/B}} Come on, my fellow white folks, we have something to confess. Out with it, friends, the biggest secret known to whites since the invention of powdered rouge: welfare is a white program. The numbers go like this: 61% of the population receiving welfare, listed as "means-tested cash assistance" by the Census Bureau, is identified as whit e, while only 33% is identified as black. These numbers notwithstanding, the Republican version of "political correctness" has given us "welfare cheat" as a new term for African American since the early days of Ronald Reagan. Our confession surely stands: white folks have been gobbling up the welfare budget while blaming someone else. But it's worse than that. If we look at Social Security, which is another form of welfare, although it is often mistaken for an individual insurance program, then whites are the ones who are crowding the trough. We receive almost twice as much per capita, for an aggregate advantage to our race of ＄10 billion a year--much more than the ＄ 3. 9 billion advantage African American gain from their disproportionate share of welfare. One sad reason: whites live an average of six years longer than African Americans, meaning that young black workers help subsidize a huge and growing "over-class" of white retirees. I do not see our confession bringing much relief. There's a reason for resentment, though it has more to do with class than with race. White people are poor too, and in numbers far exceeding any of our more generously pigmented social groups. And poverty as defined by the government is a vast underestimation of the economic terror that persists at incomes--such as ＄ 20,000 or even ＄ 40,000 and above--that we like to think of as middle class. The problem is not that welfare is too generous to blacks but that social welfare in general is too stingy to all concerned. Naturally, whites in the swelling "near poor" category resent the notion of whole races supposedly frolicking at their expense. Whites, near poor and middle class, need help too--as do the many African Americans. So we white folks have a choice. We can keep pretending that welfare is black program and a scheme for transferring our earnings to the pockets of shiftless, dark-skinned people. Or we can clear our throats, blush prettily and admit that we are hurting too--for cash assistance when we're down and out, for health insurance, for college aid and all the rest. {{U}}Racial scapegoating{{/U}} has its charms, I will admit: the surge of righteous anger, even the fun--for those inclined--of wearing sheets and burning crosses. But there are better, nobler sources of white pride, it seems to me. Remember this: only we can truly, deeply blush.

单选题 {{B}}Passage Three Glass{{/B}} (1)Since the Bronze Age, about 3000 B. C, glass has been used for making various kinds of objects. It was first made from a mixture of silica, lime, and an alkali such as soda or potash, and these remained the basic ingredients of glass until the development of lead glass in the seventeenth century. (2) When heated the mixture becomes soft and moldable and can be formed by various techniques into a vast array of shapes and sizes. The homogeneous mass thus formed by melting then cools to create glass, but in contrast to most materials formed in this way (metals, for instance), glass lacks the crystalline structure normally associated with solids, and instead retains the random molecular structure of a liquid. In effect, as molten glass cools, it progressively stiffens until rigid, but does so without setting up a network of interlocking crystals customarily associated with that process. This is why glass shatters so easily when dealt a blow. (3) Another unusual feature of glass is the manner in which its viscosity changes as it turns from a cold substance into a hot, ductile liquid. Unlike metals that flow or "freeze" at specific temperatures, glass progressively softens as the temperature rises, going through varying moldable stages until it flows like a thick syrup. Each of these stages allows the glass to be manipulated into various forms, by different techniques, and if suddenly cooled the object retains the shape achieved at that point. Glass is thus open to a greater number of heat-forming techniques than most other materials.

单选题Who were the earliest people living in North America?

单选题Which of the following can best describe the view of the author?

单选题This article deals with the natural ______ which is most interesting to everyone. A. phenomenon B. phenomena C. phenomenons D. phenomenas