单选题You can't beat it, but you don't have to join it. Maybe it got the name common cold because it's more common in winter. The fact is, though, being cold doesn't have anything to do with getting one. Colds are caused by the spread of rhinoviruses, and, at least so far, medical science is better at telling you how to avoid getting one than how to get rid of one. Children are the most common way cold viruses are spread to adults, because they have more colds than adults—an average of about eight per year. Why do kids seem so much more easily to get colds than their parents? Simple. They haven't had the opportunity to become immune to many cold viruses. There are more than 150 different cold viruses, and you never have the same one twice. Being infected by one makes you immune to it—but only it. Colds are usually spread by direct contact, not sneezing or coughing. From another person's hand to your hand and then to your nose or eyes is the most common route. The highest concentration of cold viruses anywhere is found under the thumbnails of a boy, although the viruses can survive for hours on skin or other smooth surfaces. Hygiene is your best defense. Wash your hands frequently preferably with a disinfectant soap, especially when children in your household have colds. But even careful hygiene won't ward off every cold. So, what works when a coughing, sneezing, runny nose strikes? The old prescription of two aspirins, lots of water, and bed rest is a good place to start. But you'll also find some of the folk remedies… worth using. Hot mixtures of sugar (or honey), lemon, and water have real benefits.

单选题It is implied that British people ______.

单选题 If you have been on a diet and reached your goal, chances are good that when you stop dieting you will regain all the weight you lost. After several weeks on a low-calorie diet——900 calories or fewer——the body conserves energy by slowing the speed at which it bums calories. This slow-down explains in part why your weight loss may cease after a few weeks. When you eventually return to eating a normal amount of food, your body may continue to burn calories at the slower rate, storing the remaining calories as fat. So if you are on a strict diet, your body may need fewer calories to maintain the same weight; losing weight becomes more difficult. Doctors know that as you gian weight the fat cells in your body (most of us average 30 billion of them) become enlarged. But there is a limit to how big a fat cell can get, and very fat people develop additional fat cells——sometimes more than 100 billion. It now appears that you can add fat cells at any point during your life, although the number you have is influenced by a combination of your history of dieting and your genetic makeup. Fat cells are different from other cells. They are made mostly of fat instead of protein, and apparently they never go away, even after dieting. Instead, they merely shrink. Dr. Jules Hirsch of Rockefeller University has examined the body tissue of very fat people who have lost weight, and found that it resembles that of starvation victims. Perhaps, he supposes, it is the billions of undersize, "hungry" cells that drive many formerly fat people off their diets. New research suggests that your hungry cells aren't the only signal senders that tempt you toward the refrigerator. Another criminal may be the hormone insulin. Insulin turns sugar and fat into fuel for the body. In addition, some re-searchers believe that high levels of insulin are a factor in hunger and appetite-and may drive you to overeat. Exercise helps maintain your weight and seems to bring insulin levels down, says Dr. Donald S. Robertson, a medical director. "Any weight-loss program must fail", he says, "unless it incorporates a certain amount of exercise."

单选题The author' s attitude towards the three patterns of behavior mentioned in the passage is best described as one of ______.

单选题The author implies that bacteria were investigated earlier than viruses because

单选题 Nowadays, our society is being reshaped by information technologies—computers, telecommunications networks, and other digital systems. Of course, our society has gone through other periods of dramatic change before, driven by such innovations as the steam engine, railroad, telephone, and automobile. But never before have we experienced technologies that are evolving so rapidly, altering the constraints of time and space, and reshaping the way we communicate, learn, and think. The rapid development of digital technologies creates not only more opportunities for the society but challenges to it as well. Institutions of every stripe are grappling to respond by adapting their strategies and activities. It is no exaggeration to say that information technology is completely changing the relationship between people and knowledge. But ironically, at the most knowledge-based entities—the colleges and universities—the pace of transformation has been relatively modest. Although research has been transformed by information technology in many ways, and it is increasingly used for student and faculty communications, other higher-education functions have remained almost unchanged. For example, teaching largely continues to follow a classroom-centered, seat-based paradigm. However, some major technology-aided teaching experiments are emerging, and some factors suggest that digital technologies may eventually drive significant change throughout academia. American academia has undergone significant change before. The establishment of secular education began during the 18th century and the Land-Grant College Act of 1862 resulted in another transformation. That Act created institutions serving agriculture and industries; academia was no longer just for the wealthy but charged with providing educational opportunities to the working class as well. Around the year of 1900, the introduction of graduate education began to expand the role of the university in training students for careers both scholarly and professional. Higher education has already experienced significant technology-based change, even if it currently lags other sectors in some areas. We expect that the new technology will eventually impose a profound impact on university's teaching by freeing the classroom from its physical and temporal bounds and by providing students with access to original source materials and that new learning communities driven by information technology will allow universities to better teach students how to be critical analyzers and consumers of information. The information society has greatly expanded the need for university-level education; lifelong learning is not only a private good for those who pursue it but also a social good in terms of our nation's ability to maintain a vibrant democracy and support a competitive workforce.

单选题{{B}}Passage 2{{/B}} Ever since Gregor Mendel' s famous experiments with hybrid sweet peas, it has been known that there must be unitary elements within the cells which exert control over inherited characteristics, and for a long time there was considerable speculation about what these were. These elements came to be known as genes, and although they were long treated as hypothetical constructs, a great deal of knowledge about them slowly accumulated. It came to be known, for example, that each gene had to be passed along virtually unchanged from generation to generation; that there must be many thousands of these particles in every human cell, distributed unevenly among the twenty-three pairs of chromosomes; that each gene must occupy a very definite place (locus) on its chromosome; and that each pair of homologous chromosomes had to contain homologous assortments of genes, arranged with few exceptions in precisely the same order on each member of the chromosome pail' s. A wonderfully complex and fruitful system thus emerged about an aspect of the world which no one has ever directly observed. Let us now briefly turn to some of the newly acquired insights which have greatly expanded the already impressive theory of genetics. Genes are, of course, too small to be seen even by the most powerful electron microscopes, but recent research by geneticists, microbiologists, and biochemists has rapidly advanced our information about their constitution and action. The chemical substance of which the genes and thus the chromosomes are made, is now known to be deoxyribonucleic acid (DNA), a giant molecule containing a double-spiral strand of material which embodies the genetic code. The chromosomes consist of long strands of DNA, which, although it is capable of transmitting vastly complex "code messages", is comprised of combinations of only four primary chemical subunits, or "code letters". This great insight into the structure and functioning of genetic material, which was first proposed by James D. Watson and Francis H. C. Crick in 1953, involves a new description of what genes are like. A gene is simply a specific portion of the double-spiral strand of DNA which consists of a particular combination of the code letters that spell out a particular code word. Various combinations of the four code letters, forming different code words, provide the biochemical information used in the construction of the different proteins in the cell. Many of these proteins act as enzymes. The enzymes, as has been pointed out above, are the biological catalysts which direct all the chemical or metabolic reactions that are going on continuously in all cells. These metabolic functions are, of course, the basis of all the physical growth and development of any living organism. The code is embodied in the DNA of the chromosomes and genes, but exactly how does this code deter mine the production of proteins. Obviously, the code must be transmitted to the sites at which the actual work of protein synthesis is carried out. The material which accomplishes this task is ribonucleic acid (RNA, a substance very similar to DNA and complementary to it. From the code site on the linear DNA molecule, which is the gene), RNA, the messenger, carries the code to the cellular particles out into the cytoplasm of the cell, where proteins are manufactured. This messenger RNA provides the pattern, and another type of RNA, transfer RNA, collects from within the cytoplasm the raw materials, the amino acids, from which the proteins are made. With the pattern and the materials, the proteins are formed, one step at a time. These proteins act as enzymes or biological catalysis. They exist in all living organisms and control their growth and function through the control of the chemical transformations involved in metabolism. A very large number of enzymes are present in any living creature, and the absence or malformation of any enzyme can destroy the normal sequence of metabolism of a given biochemical substance. We can thus see that genetic activity takes the form of biochemical regulation, the genes determining the formation of enzymes. In this sense, all genetic disorders are primarily metabolic defects (Garrod, 1908). A defective or changed gene will in turn produce a change in the protein with which it is associated. The only result of such a change may be a slight alteration in the function of the protein, and there may thus be little or no observable effect. If the change or defect takes place within the code message for an essential element of the protein, however, the enzyme activity of this protein may be rendered completely inactive. If this happens, the result can be grave trouble: perhaps death, serious disease, or severe mental retardation due to poisoning of the central nervous system by a metabolite that is toxic to this system. The error in enzyme synthesis may begin to be important, so that the structure of the central nervous system is faulty almost from the beginning of embryonic life, or it may become important much later in the life cycle. It is quite likely that, in the foreseeable future, many essential biochemical processes will be understood in terms of the precise genetic codes responsible for them. All of the amino acids have already yielded to such analysis; their codes have been identified. With understanding may come control and prevention, such as may be possible by administration of the lacking enzymes, dietary control of substances which the individual is unable to metabolize, or transplantation of normal tissue to the diseased individual to correct the metabolic error.

单选题WhendidAmericanscelebrateMayDay?A.The1stofMay.B.The1stofSeptember.C.The1stMondayinSeptember.D.The1stMondayinMay.

单选题The first navigational lights in the New World were probably lanterns hung at harbor en- trances. The first lighthouse was put up by the Massachusetts Bay Colony in 1716 on Little Brew- stet Island at the entrance to Boston Harbor. Paid for and maintained by "light dues" levied (征收) on ships, the original beacon was blown up in 1776. Until then there were only a dozen or so true lighthouses in the colonies. Little over a century later, there were 700 lighthouses. The first eight lanterns erected on the West Coast in the 1850's featured the same basic New England design: a Cape Cod dwelling with the tower rising from the center or standing close by. In New England and elsewhere, though, lighthouses reflected a variety of architectural styles. Since most stations in the Northeast were set up on rocky eminences (高处), enormous towers were not the rule. Some of them were made of stone and brick, others of wood or metal. Some of them stood on pilings or stilts; others were fastened to rock with iron rods. Farther south, from Maryland through the Florida Keys, the coast was low and sandy. It was often necessary to build tall towers there -- massive structures like the majestic lighthouse in Cape Hatteras, North Carolina, which was lit in 1870. 190 feet high, it is the tallest brick lighthouse in the country. Notwithstanding differences in construction appearence, most lighthouses in America shared several features: a light, living quarters, and sometimes a bell (or later a foghorn). They also had quarters, and something else in common: a keeper and usually the keeper's family. The keeper's essential task was trimming the lantern wick (灯芯) in order to maintain a steady, bright flame. The earliest keepers came from every industry -- they were seamen, farmers, mechanics, rough mill hands -- and appointments were often handed out by local customs commissioners as political plums. After the administration of lighthouse was taken over in 1852 by the United States Lighthouse Board, and agency of the Treasury Department, the keeper corps gradually became highly professional.

单选题 Questions 11--13 are based on the following passage about Emily Dickinson. You now have 15 seconds to read Questions 11--13.

单选题Questions 11—13 are based on the following passage. You now have 15 seconds to read Questions 11—13.

单选题What was the percentage of high school graduates admitted to universities in Britain thirty years ago?

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单选题It can be inferred from the passage that the temptation which the Bush administration has increasingly succumbed to comes from ______.

单选题 MALAYSIA is agog with speculation. The government, which charged a sitting minister and a prominent businessman with corruption earlier this month, says it has a list of 18 other high-profile suspects due for similar treatment. Opposition politicians say that Rafidah Aziz, the minister of trade, should be among them. She denies any wrong-doing and says she will sue her critics for defamation—a threat they claim to welcome as a chance to prove their accusations in court. Is the pervasiveness of corruption, a problem common to most countries in South-East Asia, at last getting a proper airing? The region is certainly awash with celebrated corruption cases. Joseph Estrada, the deposed president of the Philippines, is currently on trial for "economic plunder". On February 12th, Indonesia's supreme court finally ruled on a long-running embezzlement case against Akbar Tandjung, the speaker of parliament. In 2001, Thailand's constitutional court heard charges that Thaksin Shinawatra, the prime minister, had concealed some assets during an earlier stint as minister. But there is less to this flurry of righteousness than meeting the eye. For starters, prosecutors have not had much success against grand defendants like Messrs Thaksin and Tandjung. Both persuaded higher courts in overturn earlier rulings against them. Mr. Estrada, too, managed to evade impeachment while in office, and prosecutors are making heavy weather of their current case againsthim. Even the convicted Mr. Rakkiat has not yet begun his prison term, since he jumped bail and went into hiding. What is more, all the countries in the region save Singapore and Malaysia still rank in the bottom half of the most recent "Corruption Perceptions Index" compiled by Transparency International, an anti-graft watchdog. Vietnam ranked 100 out of 133 countries, Indonesia 122 and Myanmar a dismal 129. This poor showing stems in part from a lack of laws, personnel and money to combat corruption. But the resource in shortest supply is political will to tackle the problem. All countries in South -East Asia have at least one anti-corruption agency. But the ones that work best, argues Jon Quah, a professor at the National University of Singapore, are centralized, independent agencies such as Thailand's National Counter Corruption Commission. By contrast, Malaysia's Anti-Corrnption Agency reports to the government, and so is subject to political control. The Philippines, meanwhile, has adopted no fewer than seven anti-corruption laws in the past 50 years, and created 13 anti-graft agencies, according to Mr. Quah's count. Dramatic but disputed corruption allegations, such as the claim that the president's husband is managing multiple slush funds, simply get lost in all this bureaucracy.

单选题According to the passage, children tend to give more logical, complete and creative answers if adults ________.