单选题Ted got a better job and left the school before Mrs. Wolcox had him expelled.

单选题An often-used, but valuable analogy compares the immune system with an army. The defending troops are the white blood cells called lymphocytes, born in the bone marrow, billeted in the lymph nodes and spleen, and on exercise in the blood and lymph systems. A body can muster some 200,000,000 cells, making the immune system comparable in mass to the liver or brain. The lymphocytes are called to action when the enemy makes itself known. They attack anything foreign. Their job is to recognize the enemy for what it is, and then destroy it. One of the key features of the immune system is its specificity. Inoculation with smallpox provokes an attack on any smallpox virus, but on nothing else. This specificity of response depends on the lymphocyte's ability to identify the enemy correctly by the molecules on its surface, called antigens. An antigen is an enemy uniform. It can be a protein on the surface of a cold virus, or it can be a protein on the surface of a pollen grain, in which case the immune response takes the form of an allergy. An antigen can also be a protein on the surface of a transplanted organ, in which case the immune response "rejects" the transplant. Organs can therefore be transplanted only between closely related people—in whom the antigens are the same—or into people treated with a drug that suppresses the immune system, such as cyclosporin. In the 1940s, an Australian immunologist, Sir Frank Macfarlane Burnet, proposed a theory that helped explain how lymphocytes recognize and are activated by specific foreign antigens. The clonal selection theory as it was called, suggested that the innate immune system was not a homogeneous mass of more or less identical lymphocytes, but rather was made up of millions of different families called clones. The members of each clone carry on their surfaces a receptor that is capable of identifying and binding to just one foreign antigen (or a part of it called the determinant). Thus, when a foreign body carrying that antigen appears, the antigen binds to the receptor of only those lymphocyte clones which are capable of recognizing it. Once the antigen binds to the receptor, it stimulates the lymphocyte to divide, which generates more identical copies of itself. These clone members then attack the foreign entity which carries the antigen. This implies that the immune system works on a "ready-made" basis. A person's immune system inherits the knowledge of all foreign antigens to which it might be exposed. The sum of this inheritance increases as new threats are met.

单选题The two countries were fighting severely to ______ every inch of the land. A. intervene B. contest C. imperil D. inhabit

单选题When he lived in Tibet in 1950s, radio was the only means he had to keep ______ of current events in the country.(2004年武汉大学考博试题)

单选题{{B}}Text 2{{/B}} Imagine a world in which there was suddenly no emotion—a world in which human beings could feel no love or happiness, no terror or hate. Try to imagine the consequences of such a transformation. People might not be able to stay alive: knowing neither joy nor pleasure, neither anxiety nor fear, they would be as likely to repeat acts that hurt them as acts that were beneficial. They could not learn: they could not benefit from experience because this emotionless world would lack rewards and punishments. Society would soon disappear: people would be as likely to harm one another as to provide help and support. Human relationships would not exist: in a world without friends or enemies, there could be no marriage, affection among companions, or bonds among members of groups. Society's economic underpinnings would be destroyed: since earning $10 million would be no more pleasant than earning $10, there would be no incentive to work. In fact, there would be no incentives of any kind. For as we will see, incentives imply a capacity to enjoy them. In such a world, the chances that the human species would survive are next to zero, because emotions are the basic instrument of our survival and adaptation. Emotions strcture the world for us in important ways. As individuals, we categorize objects on the basis of our emotions. True we consider the length, shape, size, or texture, but an object's physical aspects are less important than what it has done or can do to us—hurt us, surprise us, anger us or make us joyful. We also use categorizations coloured by emotions in our families, communities, and overall society. Out of our emotional experiences with objects and events comes a social feeling of agreement that certain things and actions are "good" and others are "bad", and we apply these categories to every aspect of our social life—from what foods we eat and what clothes we wear m how we keep promises and which people our group will accept. In fact, society exploits our emotional reactions and attitudes, such as loyalty, morality, pride, shame, guilt, fear and greed, in order to maintain itself. It gives high rewards to individuals who perform important tasks such as surgery, makes heroes out of individuals for unusual or dangerous achievements such flying fighter planes in a war, and uses the legal and penal system to make people afraid to engage in antisocial acts.

单选题By now Dad was sixty-five, and what little lenience he may once have possessed had long since hardened into______inflexibility. A. compassionate B. friendly C. remorseful D. steely

单选题Which of the following has contributed to the writer's divorce?

单选题{{B}}Passage Five{{/B}} The Intergovernmental Panel on Climate Change concluded that global warming is no game. They provide evidence that heat-trapping gases related to human activities--such as carbon dioxide from burning coal, oil, and gas--are in part driving global warming by increasing the amount of the sun's heat trapped in the earth's atmosphere. This extra heat is making the global climate system unstable. Because the climate system is complex, scientists cannot predict precisely how much and how fast the climate will change. But sophisticated computer simulations project a range of scenarios for increases in average surface temperature between 1.8° and 6.3°F (1° and 3.5℃) by the year 2100. (Bear in mind that seemingly small changes in temperature can produce major changes in climate. During the last Ice Age, global temperatures were only 5° to 9°F cooler than they are today, but that was sufficient to bury what is now Canada, New York, and New England under a kilometer of ice.) Within the next 20 years, various regions of the world may experience severe changes in climate. Some may be vulnerable to longer droughts, others to more coastal flooding, and many to more frequent bouts of extreme weather. And if global warming continues unchecked, we could well see greater risk to human health as diseases previously found in tropical areas spread to higher latitudes and elevations. Also, insect-borne diseases such as malaria and dengue fever are already moving northward from tropical regions. Forests and wetlands provide critical benefits to human health, by filtering our air and water, and to human welfare, by providing opportunities for recreation and commerce. Changes in regional climate put many such ecosystems at risk by hindering their ability to grow and regenerate. The survival of these wetlands--often are as of high biodiversity that also provide protection against floods--depends on the water's temperature, flow, and level. Scientists are confident that global warming will reduce the area of wetlands and change their distribution. Arctic and subarctic wetlands, which are critical refuge and breeding grounds for large numbers of migratory species, are among the most vulnerable. Other coastal zone habitats--including marshes, mangroves, coral reefs and atolls, and river deltas--will also be threatened. Avoiding these costly damages justifies immediate action to turn off the road to ruin. Scientists and economists have identified many technically feasible, cost-effective opportunities for emissions reductions, including energy-efficiency measures, advanced vehicle technologies, cuts in oil and coal subsidies, and investments in clean, renew-able energy sources like wind and solar power. To take advantage of these opportunities, governments and industry must work together. The Union of Concerned Scientists (UCS) is working to advance policies that will turn our society aside from the ruinous road to a global warming future.

单选题Within the {{U}}bounds {{/U}}of given data, the biographer seeks to illuminate factual information about a person and transform it into insight.

单选题The passage mainly discloses ______.

单选题From the passage we learn that many renters disagree with ______.

单选题The criminal ______ past a guard and managed to escape.(2008年北京航空航天大学考博试题)

单选题Publishers are using a blitz of advertising, Web sites, as well as traditional methods to ______for elusive teens market. A. angle B. allow C. budget D. care

单选题To broaden their voting appeal in the Presidential election of 1796, the Federalists selected Thomas Pinckney, a leading South Carolinian, as running mate for the New Englander John Adams. But Pinckney's Southern friends chose to ignore their party's intentions and regarded Pinckney as a Presidential candidate, creating a political situation that Alexander Hamilton was determined to exploit. Hamilton had long been wary of Adams' stubbornly independent brand of politics and preferred to see his running mate, over whom he could exert more control, in the President's chair. The election was held under the system originally established by the Constitution. At that time there was but a single tally, with the candidate receiving the largest number of electoral votes declared President and the candidate with the second largest number declared Vice President. Hamilton anticipated that all the Federalists in the North would vote for Adams and Pinckney equally in an attempt to ensure that Jefferson would not be either first or second in the voting. Pinckney would be solidly supported in the South while Adams would not. Hamilton concluded if it were possible to divert a few electoral votes from Adams to Pinckney, Pinckney would receive more than Adams, yet both Federalists would outpoll Jefferson. Various methods were used to persuade the electors to vote as Hamilton wished. In the press, anonymous articles were published attacking Adams for his monarchial tendencies and Jefferson for being overly democratic, while pushing Pinckney as the only suitable candidate. In private correspondence with state party leaders the Hamiltonians encouraged the idea that Adams' popularity was slipping, that he could not win the election, and that the Federalists could defeat Jefferson only by supporting Pinckney. Had sectional pride and loyalty not run as high in New England as in the deep South, Pinckney might well have become Washington's successor. New Englanders, however, realized that equal votes for Adams and Pinckney in their states would defeat Adams; therefore, eighteen electors scratched Pinckney's name from their ballots and deliberately threw away their second votes to men who were not even running. It was fortunate for Adams that they did, for the electors from South Carolina completely abandoned him, giving eight votes to Pinckney and eight to Jefferson. In the end, Hamilton's interference in Pinckney's candidacy lost even the Vice-Presidency of South Carolina. Without New England's support, Pinckney received only 59 electoral votes, finishing third to Adams and Jefferson. He might have been President in 1797, or as Vice President a serious contender for the Presidency in 1800; instead, stigmatized by a plot he had not devised, he served a brief term in the United States Senate and then dropped from sight as a national influence.

单选题Public speaking fills most people with dread. Humiliation is the greatest fear; self- exposure and failing to appeal to the audience come a close second. Women hate it most, since girls are pressurized from an early age to be concerned with appearances of all kinds. Most people have plenty of insecurities, and this seems like a situation that will bring them out. If you were under pressure to be perfect, you are terrified of falling in the most public of ways. Extroverts, on the contrary, will feel less fear before the ordeal. It does not mean they will necessarily do it better. Some very shy people manage to shine. When I met the British comedian Julian Clary, he was shy and cautious, yet his TV performances are perfect. In fact, personality is not the best predictor of who does it well. Regardless of what you are like in real life, the key seems to be to act yourself. Actual acting, as in performing the scripted lines of a character other than yourself, does not do the job. While politicians may limit damage by having carefully rehearsed, written scripts to speak from, there is always a hidden awareness among the audience that the words might not be true. Likewise, the incredibly perfect speeches of many American academics are far from natural. You may end up buying their book on the way out, but soon afterwards, it is much like fast food, and you get a nameless sense that you"ve been cheated. Although, as Earl Spencer proved at his sister Princess Diana"s funeral, it is possible both to prepare every word and to act naturally. A script rarely works and it is used to help most speakers. But, being yourself doesn"t work either. If you spoke as if you were in your own kitchen, it would be too authentic, too unaware of the need to communicate with an audience. I remember going to see British psychiatrist R. D. Laing speak in public. He behaved like a seriously odd person, talking off the top of his head. Although he was talking about madness and he wrote on mental illness, he seemed to be exhibiting rather than explaining it. The best psychological place from which to speak is an unselfconscious self- consciousness, providing the illusion of being natural. Studies suggest that this state of "flow", as psychologists call it, is very satisfying.

单选题The Pullman Strike of 1894 tied up transportation and was finally ended only by government intervention. A. relied upon B. hindered C. linked with D. imitated

单选题Your complaint is being ______ ; when we have anything to report we'll write to you again.

单选题The groom's hand ______ the soft mane of the horse.