单选题What does, according to the author, economic welfare consist of?

单选题In addition to rice, we need to ______ our diet with fish, meat and vegetable.

单选题The survival ______ of some wild animals is not very high as they are ruthlessly hunted for their skins. A. standard B. scale C. ratio D. rate

单选题A newspaper______ is an amusing drawing, usually about some events in the news.

单选题One of the most damaging plant parasites is the stem eelworm. A. harmful B. elegant C. versatile D. prevalent

单选题These notes, which are relevant to international students, are intended to supplement information given in the Guide and should be read ______ the appropriate sections on accommodation, applications, entrance requirements, etc.

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 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 {{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Our research has not shown us anything so far, so there is little ______ to continue with it. A. impatience B. incentive C. impulse D. initiative

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

单选题Japan is a______society of one nationality and a few underrepresented minority groups, such as the ethnic Chinese and Koreans.

单选题The number of stay-at-home fathers reached a record high last year, new figures show, as families saw a(n) ______ in female breadwinners. A. raise B. rise C. arise D. increase

单选题Forests are delicate systems that if disturbed can be permanently destroyed.

单选题She was extremely lucky; when her great-uncle died, she ______ a fortune. A. came by B. came over C. came into D. came about