单选题There is also a fat lady who asked Alex ______ he wanted something to eat.

单选题The human Y chromosome—the DNA chunk that makes a man a man—has lost so many genes over evolutionary time that some scientists have suspected it might disappear in 10 million years. But a new study says it'll stick around. Researchers found no sign of gene loss over the past 6 million years, suggesting the chromosome is "doing a pretty good job of maintaining itself," said researcher David Page of the Whitehead Institute for Biomedical Research in Cambridge, Mass. That agrees with prior mathematical calculations that suggested the rate of gene loss would slow as the chromosome evolved, Page and study co-authors note in Thursday's issue of the journal Nature. And, they say, it clashes with what Page called the "imminent demise" idea that says the Y chromosome is doomed to extinction. The Y appeared 300 million years ago and has since eroded into a dinky chromosome, because it lacks the mechanism other chromosomes have to get rid of damaged DNA. So mutations have disabled hundreds of its original genes, causing them to be shed as useless. The Y now contains only 27 genes or families of virtually identical genes. In 2003, Page reported that the modern-day Y has an unusual mechanism to fix about half of its genes and protect them from disappearing. But he said some scientists disagreed with his conclusion. The new paper focuses on a region of the Y chromosome where genes can't be fixed that way. Researchers compared the human and chimpanzee versions of this region. Humans and chimps have been evolving separately for about 6 million years, so scientists reasoned that the comparisons would reveal genes that have become disabled in one species or the other during that time. They found five such genes on the chimp chromosome, but none on the human chromosome, an imbalance Page called surprising. "It looks like there has been little if any gene loss in our own species lineage in the last 6 million years," Page said. That contradicts the idea that the human Y chromosome has continued to lose genes so fast it'll disappear in 10 million years, he said. "I think we can with confidence dismiss … the 'imminent demise' theory," Page said. Jennifer A. Marshall Graves of the Australian National University in Canberra, a gene researcher who argues for eventual extinction of the Y chromosome, called Page's work "beautiful" but said it didn't shake her conviction that the Y is doomed. The only real question is when, not if, the Y chromosome disappears, she said. "It could be a lot shorter than 10 million years, but it could be a lot longer," she said. The Y chromosome has already disappeared in some other animals, and "there's no reason to expect it can't happen to humans," she said. If it happened in people, some other chromosome would probably take over the sex-determining role of the Y, she said.

单选题In its broadest sense, attribution theory is concerned with how ordinary people make sense of the world and it______ more controllable and predictable by making attributions as to the causes of people's behaviors and events.(2002年复旦大学考博试题)

单选题Henry Kissinger may be the most successful, certainly the most flamboyant, Secretary of State to hold that office in modern times. When he was appointed in the late 1960's, there were no American ties with Communist China, Vietnam and Berlin seemed ready to draw the United States into a third world war, and Russia was seen as "the enemy". But all this has changed, and Henry Kissinger caused much of the change; in 1971, he made his first trip to China, a trip that was the beginning of the current ties between the United States and China. He brought the United States and Russia closer together on major issues by the policy he called "detente", literally meaning a relaxation. His philosophy was always to talk and to bring together. With these two policies, Kissinger did much to draw attention away from any possible Russia-American friction. In 1973 he made his first visit to Egypt. Here he was able to begin U.S. relations with Egypt. He used his contact later to begin the sort of talks that the American press called "shuttle diplomacy". For ninety-nine days, he "shuttled" back and forth on flights between Cairo and Jerusalem to work out a step-by-step withdrawal of Israeli troops from the Sinai desert. His wit, his careful approach to detail, and his presence made "shuttle diplomacy" work. It was the only successful approach to Mid-east peace in the thirty years since the state of Israel was founded. Another major work was the Strategic Arms Limitation Talk. Though his term in office passed with the treaty unsigned, Kissinger left a draft of the treaty to which the Russians had already agreed. The SALT treaty spelled out a one-tenth reduction in nuclear arms, a major accomplishment by any standard, even if one does not consider all the other conditions and limitations included in the treaty. Even though he successfully helped bring an end to the Vietnam War, Kissinger's final days in office were affected, as was the entire executive branch in one way or another, by the scandals of the Nixon White House. Kissinger's critics point to his role in placing wiretaps on the phones of reporters and officials and to what they consider his "high-handed" approach to setting foreign policy. But Kissinger, during the last few months of the Nixon presidency, limited the effects of American domestic problems on our foreign policy. He continued talks in the Middle East. He continued close contact with the Soviet Union. History will decide in the final view, as Kissinger--and many presidents--often said, on the value of his service. Whatever they decide, whether his actions are finally to be considered wise or foolish, he had a personal vision that will he difficult to match.

单选题My business brings ______ such a big sum of 200,000 yuan for "the Hope Project".A. inB. aboutC. outD. back

单选题It is imperative that students______their term papers on time.(中南大学2007年试题)

单选题If you ______ such a long time to get dressed, we'd have been there by now.

单选题Homework has never been terribly popular with students and even many parents, but in recent years it has been particularly scorned. School districts across the country, most recently Los Angeles Unified, are revising their thinking on his educational ritual. Unfortunately, L. A. Unified has produced an inflexible policy which mandates that with the exception of some advanced courses, homework may no longer count for more than 10% of a student"s academic grade. This rule is meant to address the difficulty that students from impoverished or chaotic homes might have in completing their homework. But the policy is unclear and contradictory. Certainly, no homework should be assigned that students cannot do without expensive equipment. But if the district is essentially giving a pass to students who do not do their homework because of complicated family lives, it is going riskily close to the implication that standards need to be lowered for poor children. District administrators say that homework will still be a part of schooling, teachers are allowed to assign as much of it as they want. But with homework counting for no more than 10% of their grades, students can easily skip half their homework and see vey little difference on their report cards. Some students might do well on state tests without completing their homework, but what about the students who performed well on the tests and did their homework? It is quite possible that the homework helped. Yet rather than empowering teachers to find what works best for their students, the policy imposes a flat, across-the-board rule. At the same time, the policy addresses none of the truly thorny questions about homework. If the district finds homework to be unimportant to its students" academic achievement, it should move to reduce or eliminate the assignments, not make them count for almost nothing. Conversely, if homework matters, it should account for a significant portion of the grade. Meanwhile this policy does nothing to ensure that the homework students receive is meaningful or appropriate to their age and the subject, or that teachers are not assigning more than they are willing to review and correct. The homework rules should be put on hold while the school board, which is responsible for setting educational policy, looks into the matter and conducts public hearings. It is not too late for L. A. Unified to do homework right.

单选题--What' s wrong? --Nothing serious. I'm just ______ busy. A. much B. more C. too much D. far too

单选题When school officials in Kalkaska, Michigan, closed classes last week, the media flocked to the story, portraying the town"s 2,305 students as victims of stingy taxpayers. There is some truth to that: the property-tax rate here is one-third lower than the state average. But shutting their schools also allowed Kalkaska"s educators and the state"s largest teachers" union, the Michigan Education Association, to make a political point. Their aim was to spur passage of legislation Michigan lawmakers are debating to increase the state"s share of school funding. It was no coincidence that Kalkaska shut its schools two weeks after residents rejected a 28 percent property-tax increase. The school board argued that without the increase it lacked the $1.5 million needed to keep schools open. But the school system had not done all it could to keep the schools open. Officials declined to borrow against next year"s state aid, they refused to trim extracurricular activities and they did not consider seeking a smaller—perhaps more acceptable—tax increase. In fact, closing early is costing Kalkaska a significant amount, including $600,000 in unemployment payments to teachers and staff and $250,000 in lost state aid. In February, the school system promised teachers and staff two months of retirement payments in case schools closed early, a deal that will cost the district $275,000 more. Other signs suggest school authorities were at least as eager to make a political statement as to keep schools open. The Michigan Education Association hired a public relations firm to stage a rally marking the school closings, which attracted 14 local and national television stations and networks. The president of the National Education Association, the MEA"s parent organization, flew from Washington, D.C., for the event. And the union tutored school officials in the art of television interviews. School supervisor Doyle Disbrow acknowledges the district could have kept schools open by cutting programs but denies the moves were politically motivated. Michigan lawmakers have reacted angrily to the closings. The state Senate has already voted to put the system into receivership and reopen schools immediately; the Michigan House plans to consider the bill this week.

单选题The examples of GE and Staples in the first paragraph are to show that both companies

单选题Writing stories and articles ______ what she enjoys most.A. isB. have beenC. wasD. were

单选题Marie Curie took little notice ______ the honours that were given to her in her later years.A. ofB. onC. aboutD. chance

单选题TCP stands for ______. A．Technology Concept Principle B．Technique Control Protocol C．Technical Connected Procedure D．Transmission Control Protocol

单选题If she doesn't tell him the truth now, he'll simply keep on asking until she ______. A. does B. has done C. will do D. would

单选题[此试题无题干]

单选题You can't vote until you have______ all the formal conditions.

单选题In 1998 consumers could purchase virtually anything over the Internet. Books, compact discs, and even stocks were available from World Wide Web Sites that seemed to spring up almost daily. A few years earlier, some people had predicted that consumers accustomed to shopping in stores would be reluctant to buy things that they could not see or touch in person. For a growing number of time-starved consumers, however, shopping from their home computer was proving to be a convenient alternative to driving to the store. A research estimated that in 1998 US consumers would purchase $ 7.3 billion of goods over the Internet, double the 1997 total. Finding a bargain was getting easier, owing to the rise of online auctions and Web sites that did comparison shopping on the Internet for the best deal. For all the consumer interest, retailing in cyberspace was still a largely unprofitable business, however. Internet pioneer Amazon. com, which began selling books in 1995 and later branched into recorded music and videos, posted revenue of $153.7 million in the third quarter, up from $37.9 minion in the same period of 1997. Overall, however, the company's loss widened to $45.2 million from $9.6 million, and analysts did not expect the company to turn a profit until 2001. Despite the great loss, Amazon. com had a stock market value of many billions, reflecting investors' optimism about the future of the industry. Internet retailing appealed to investors because it provided an efficient means for reaching millions of consumers without having the cost of operating conventional stores with their armies of salespeople. Selling online carried its own risks, however. With so many companies competing for consumers' attention, price competition was intense and profit margins thin or nonexistent. One video retailer sold the hit movie Titanic for $9.99, undercutting the $19.99 suggested retail price and losing about $6 on each copy sold. With Internet retailing still in its initial stage; companies seemed willing to absorb such losses in an attempt to establish a dominant market position.