单选题At some time around 2300BC, give or take a century or two, a large number of the major civilizations of the world collapsed, in Mesopotamia, Egypt, Israel, Anatolia, and Greece, as well as in Afghanistan and China. All of them the first urban civilizations fell into rain at more or less the same time. A thousand years later, around 1200BC, many of the civilizations of the same regions again collapsed at about the same time. The reasons for these widespread and apparently simultaneous disasters which coincided with changes to cultures and societies elsewhere, such as in Britain, have long been a fascinating mystery. Traditional explanations included warfare, famine, and more recently systems collapse, but the apparent absence of direct archaeological or written evidence for causes, as opposed to effects, has led many archaeologists and historians into a resigned assumption that no definite explanation can be found. Over the past 15 years, however, a new type of 'natural disaster' has been proffered which is beginning to be regarded by many scholars as the most probable single explanation for widespread and simultaneous cultural collapse. The new theory has been advanced largely by astronomers and remains largely unknown by archaeologists (notable exceptions include Professor Baillie of Belfast and Dr. Euan Mackie in Glasgow). The theory postulates that the disasters were caused by the impact of comets or other types of cosmic debris on the Earth. French archaeologist Chude Schaeffer, in 1948, published his analysis and compared the destruction layers of more than 40 archaeological sites. He was the first scholar to detect that all of the sites had been totally destroyed several times in the Early, Middle and Late Bronze Age, apparently simultaneously. Since the damage did not show signs of military or other human involvement, and, in any case, was too excessive, he argued that repeated seismic activity might have been responsible. Schaeffer was not taken seriously in 1948, but since then natural scientists have found widespread and unambiguous evidence for abrupt climate change, sudden sea level changes, catastrophic inundations, and seismic activity at several periods since the last Ice Age, particularly around 2300BC. Areas such as the Sahara, which were once farmed, became deserts. Tree rings show disastrous conditions at 2350BC. In Mesopotamia the land appears to have been inundated, devastated, or totally burned. Scholars who, following Schaeffer, favor earthquakes as the principal cause of civilization collapse, argue that the world can expect earthquakes every 1000 ～2000 years, leading to abandonment of sites; while scholars who prefer climate change as the principal cause argue that severe droughts caused agriculture to fail and that .societies inexorably fell apart as a result. The question remained what caused the climate change or the earthquakes. By the late 1970's British astronomers Clube and Napier of Oxford University had begun to investigate cometary impact as the ultimate cause. In 1980, the Nobel prize-winning chemist Luis Alvarez and his colleagues published their paper arguing that a cosmic impact had caused the extinction of the dinosaurs. He showed that large amounts of iridium found in geological layers from the time of the dinosaurs had a cosmic origin. Alvarez's paper stimulated further research by Clube and Napier, Professor Mark Bailey, Duncan Steel and Sir Fred Hoyle. All now support the theory of cometary impact and what is now known as the British School of Coherent Catastrophism.

单选题In the Chinese household, grandparents and other relatives play ______ roles in raising children.

单选题Every modern government, liberal or otherwise, has a specific position in the field of ideas; its stability is {{U}}vulnerable{{/U}} to critics in proportion to their ability and persuasiveness.

单选题In a divorce, the mother usually is granted ______of her children. A.support B.retention C.perseverance D.custody

单选题The whole program is well designed, but some details need further ______ by some experts. A. proofing B. modifying C. demonstrating D. polishing

单选题The computer can ______ stored information in a matter of minutes.

单选题A person' s psychological______ has much to do with his or her happiness in life.

单选题A series of border incidents inevitably led the two countries to war. A. distinctly B. unavoidably C. regularly D. actually

单选题Walking through my train yesterday, staggering from my seat to the buffet and back, I counted five people reading Harry Potter novels. Not children- these were real grown-ups reading children's books, Maybe that would have been understandable. If these people had jumped whole-heartedly into a second childhood it would have made more sense. But they were card-carrying grown-ups with laptops and spreadsheets returning from sales meetings and seminars. Yet they chose to read a children's book. I don't imagine you'll find this headcount exceptional. You can no longer get on the London Tube and not see a Harry Potter book. Nor is it just the film; these throwback readers were out there in droves long before the movie campaign opened. So who are these adult readers who have made J.K. Rowling the second-biggest female earner in Britain (after Madonna)? As I have tramped along streets knee-deep in Harry Potter paperbacks, I've mentally slotted them into three groups. First come the Never-Readers, whom Harry has enticed into opening a book. Is this a bad thing? Probably not. Writing has many advantages over film, but it can never compete with its magnetic punch. If these books can re-establish the novel as a thrilling experience for some people, then this can only be for the better. If it takes obsession-level hype to lure them into a bookshop. that's fine by me. But will they go on to read anything else? Again, we can only hope. The second group are the Occasional Readers. These people claim that tiredness, work and children allow them to read only a few books a year. Yet now--to be part of the crowd, to say they've read it- they put Harry Potter on their oh-so-select reading list. It's infuriating, and maddening. Yes, I'm a writer myself, currently writing difficult, unreadable, hopefully unsettling novels, but there are so many other good books out there, so much rewarding, enlightening, enlarging works of fiction for adults; and yet these sad cases are swept along by the hype, the faddism, into reading a children's book. The third group are the Regular Readers, for whom Harry is sandwiched between McEwan (英国当代作家) and Balzac, Roth (德国现代诗人) and Dickens. This is the real baffler--what on earth do they get out of reading it? Why bother? But if they call rattle through it in a week just to say they've been there- like going to Longleat (朗利特山庄，英国名胜)or the Eiffel Tower--the worst they're doing is encouraging others.

单选题The department chairman______with thanks the assistance of all the faculty members for getting the celebration ready in a short time.

单选题Being afraid of the enemy's attack, he ______ motionless in the grass for half an hour.

单选题When a member of an ethnic minority group acquires the behavior patterns, lifestyles, values, and language of the mainstream culture we say that he or she has become culturally assimilated. Since the dominant group controls most of the social, economic, and political institutions in a society, members of ethnic minority groups must acquire its cultural traits to move up the social and economic ladder. When studying this concept, it is important to learn that although non-White ethnic minorities may become totally assimilated culturally, they will still be victims of discrimination and racism because of their different physical characteristics. A widespread myth is that Mexican Americans and Afro-Americans experience discrimination because they often have meager educations and live in ghettos. Even though it is true that many Blacks and Mexican Americans are members of the lower socioeconomic classes, and that all lower-class individuals are treated differently than middle-and upper-class people, it is also true that Blacks and Chicanos with high educations and incomes frequently experience discrimination because of their color. Since American racism is based largely on skin color, no degree of cultural assimilation eliminates it. Some discussion of forced assimilation and cultural genocide should take place when students study cultural assimilation. Assimilation often occurs when a minority group "voluntarily" acquires the behavior patterns and lifestyles of dominant group to attain social mobility and occupational success. I use the word voluntarily here somewhat reluctantly because without some degree of cultural assimilation, a group that is very different culturally may not be able to survive in a particular culture. However, in the history of the United States, some forms of cultural assimilation that took place were totally nonvoluntary and might be called forced assimilation because the cultures of certain groups were deliberately destroyed (cultural genocide). These groups were forced to acquire the language, lifestyles, and values of the dominant culture. Individuals and groups who refused to accept the dominant culture were sometimes the victims of severe punishments, such as death. The cultures of African groups were deliberately destroyed by the slave masters. This cultural destruction began on the slave ships. It seems that systematic and deliberate attempts were made to destroy Indian cultures. These efforts were highly successful since many of the cultural elements of these groups now exist only in the pages of history, and sometimes not even there since they were often destroyed before they could be recorded.

单选题Many people seem to think that science fiction is typified by the covers of some of the old pulp magazines: the Bug-Eyed Monster, embodying every trait and feature that most people find repulsive, is about to grab, and presumably ravish, a sweet, blonde, curvaceous, scantily-clad Earth girl. This is unfortunate because it demeans and degrades a worthwhile and even important literary endeavor. In contrast to this unwarranted stereotype, science fiction rarely emphasizes sex, and when it does, it is more discreet than other contemporary fiction. Instead, the basic interest of science fiction lies in the relation between man and his technology and between man and the universe. Science fiction is a literature of change and a literature of the future, and while it would be foolish to claim that science fiction is a major literary genre at this time, the aspects of human life that it considers make it well worth reading and studying ——for no other literary form does quite the same things. The question is: what is science fiction? And the answer must be, unfortunately, that there have been few attempts to consider this question at any length or with much seriousness; it may well be that science fiction will resist any comprehensive definition of its characteristics. To say this, however, does not mean that there are no ways of defining it nor that various facets of its totality cannot be clarified. To Begin, the following definition should be helpful: science fiction is a literary sub-genre which postulates a change (for human beings) from conditions as we know them and follows the implications of these changes to a conclusion. Although this definition will necessarily be modified and expanded, and probably changed, in the course of this exploration, it covers much of the basic groundwork and provides a point of departure. The first point ——that science fiction is a literary sub-genre ——is a very important one, but one which is often overlooked or ignored in most discussions of science fiction. Specifically, science fiction is either a short story or a novel. There are only a few dramas which could be called science fiction, with Karel Capek's RUR (Rossum's Universal Robots) being the only one that is well known; the body of poetry that might be labeled science fiction is only slightly larger. To say that science fiction is a sub-genre of prose fiction is to say that it has all the basic characteristics and serves the same basic functions in much the same way as prose fiction in general ——that is, it shares a great deal with all other novels and short stories. Everything that can be said about prose fiction, in general applies to science fiction. Every piece of science fiction, whether short story or novel, must have a narrator, a story, a plot, a setting, character, language, and theme. And like any prose, the themes of science fiction are concerned with interpreting man's nature and experience in relation to the world around him. Themes in science fiction are constructed and presented in exactly the same ways that themes are dealt with in any other kind of fiction. They are the result of a particular combination of narrator, story, plot, character, setting, and language. In short, the reasons for reading and enjoying science fiction, and the ways of studying and analyzing it, are basically the same as they would be for any other story or novel.

单选题______ find out who the murderer was.

单选题The girl ______ when she couldn't answer the question in the presence of all her classmates.

单选题A person's calorie requirements vary ______ his life.

单选题As a law graduate, he ought to know that eyewitness______ is notoriously unreliable, especially so when the witness is not an expert.

单选题Once upon a time, innovation at Procter & Gamble flowed one way: from the United States outward. While the large Cincinnati-based corporation was no stranger to foreign markets, it usually sold them products that were already familiar to most Americans. Many Japanese families, for instance, swaddle their babies in Pampers diapers, and lots of Venezuelans brush their teeth with Crest. And of course (company executive assumed) American at home wanted these same familiar, red-white and blue brands. We might buy foreign-made cars, or chocolates, or cameras but household cleaners and detergents? Recently, however, P&G broke with this long-standing tradition. Ariel, a P&G laundry detergent, was born overseas, and is a familiar sight on store shelves in Europe and Latin America. Now bilingual packages of Ariel Ultra, a super-concentrated cleaner, are appearing on supermarket shelves in Los Angeles. Ariel"s appearance in the United States reflects demographic changes making Hispanics the nation"s fastest-growing ethnic group. Ariel is a hit with this population. In fact, many Mexican immigrants living in Southern California have been "importing" Ariel from Tijuana, Mexico. "Hispanics knew this product and wanted it," says P&G spokeswoman Marie Salvado. "We realized that we couldn"t convince them to buy (our) other laundry detergents." P&G hopes that non-Hispanic consumers will give Ariel a try too. Ariel"s already strong presence in Europe may provide a springboard for the company to expand into other markets as well. Recently P&G bought Rakona, Czechoslovakia"s top detergent maker. Ariel, currently a top seller in Germany, is likely to be one of the first new brands to appear in Czech supermarkets. And Ariel is not the only foreign idea that the company hopes to transplant back to its home territory. Chinch, an all-purpose spray cleaner similar to popular European products, is currently being test-marketed in California and Arizona. Traditionally Americans have used separate cleaners for different types of surfaces, but market research shows that American preferences are becoming more like those in other countries. Insiders note that this new reverse flow of innovation reflects more sweeping changes at Procter & Gamble. The firm has hired many new Japanese, German, and Mexican managers who view P&G"s business not as a one-way flow of American ideas, but a two-way exchange with other markets. Says Bonita Austin of the investment firm Wertheim-Schroeder, "When you met with P&G"s top managers years ago, you wouldn"t have seen a single foreign face." Today "they could even be in the majority." As Procter & Gamble has found, the United States is no longer an isolated market. Americans are more open than ever before to buying foreign-made products and to selling U. S.-made products overseas.