问答题 Practice 10　　Every British citizen who is employed (or self-employed) is obliged to pay a weekly contribution to the national insurance and health schemes. An employer also makes a contribution for each of his employees, and the Government too pays a certain amount. This plan was brought into being in 1948. Its aim is to prevent anyone from going without medical services, if he needs them, however poor he may be; to ensure that a person who is out of work shall receive a weekly sum of money to subsist on; and to provide a small pension for those who have reached the age of retirement.　　Everyone can register with a doctor of his choice and if he is ill he can consult the doctor without having to pay for the doctor's service, although he has to pay a small charge for medicines. The doctor may, if necessary, send a patient to a specialist, or to hospital~ in both cases treatment will be given without any fees being payable. Those who wish may become private patients, paying for their treatment, but they must still pay their contributions to the national insurance and health schemes.

问答题 Practice 4　　Both language and culture are learned by children without special organized programs of instruction, but motivation to learn is very high since language is the most effective means for a child to obtain what he or she wants. If the learning of a new language begins before lower adolescence, one is likely to be able to speak such a language with complete naturalness, but if learned after upper adolescence some hangover of a mother-tongue feature is very likely to persist. But not only do languages exhibit such learning patterns, but so do cultural traits, for example, shaking hands, kissing, and embracing.　　Although many persons assume that languages exist in dictionaries and grammars, in fact they only exist in people’s heads. But this is equally true of cultural traits, which indicate clearly a they only exist in people’s heads. But this is equally true of cultural traits, which indicate clearly a person’s value system when crucial decisions need to be made before there is any time to think about alternatives, for example, diving into a flooding stream to rescue a drowning child.

问答题 Practice 1　　The point is that, apart from many of the polygraphers being unqualified, the tests themselves are by no means free from error, primarily because they discount human imagination and ingenuity. Think of all those perfectly innocent people, with nothing to be afraid of, who blush and stammer when a customs officer asks them if they have anything to declare. Fear, and a consequently heightened electrical response, may not be enough to establish guilt. It depends on whether the subject is afraid of being found out or afraid of being wrongfully convicted. On the other hand, the person who is really guilty and whose past experience has prepared him for such tests can distort the results by anticipating the crucial questions or deliberately giving exaggerated responses to neutral ones!　　The success rate of up to 90% claimed for lie detectors is misleadingly attractive. If we refer such a figure to a company with 500 employees, twenty of whom are thieves, the lie detector could catch 18 of them but in doing so would place 32 innocent employees under suspicion.

问答题 Practice 5　　If you think American cooking means opening a package and tossing the contents into the microwave, think again. On the one hand, it's true that Americans thrive on cold cereal for breakfast, sandwiches for lunch and instant dinners. From busy homemakers to professional people, many Americans enjoy the convenience of prepackaged meals that can be ready to serve in 10 minutes or less. On the other hand, many Americans recognize the value of cooking skills. Most Americans will admit that there's nothing better than a good home-cooked meal.　　Probably every cook has his or her own cooking style. But there are some basic techniques and principles that most people follow. For example, baking is a primary method of preparing food in America. The dinner menu often has roast meats and other baked goods. For that reason, Americans would find it next to impossible to live without an oven. American cooks give special attention to the balance of foods, too. In planning a big meal they try to include a meat, a few vegetables, some bread or pasta and often a dessert. They also like to make sure the meal is colorful. Having several different colors of food on the plate usually makes for a healthy meal.

问答题 Practice 4　　The other kind of bank—the Bank of the United States was simultaneously a commercial bank and a quasi-public central bank. The First Bank of the United States, chartered by the Congress in 1791, owed its existence to Alexander Hamilton who, shortly after becoming Secretary of the Treasury, showed remarkable insight into the financial problems of the young country and the economic implications of banking. The First Bank of the United States operated much like a private bank. But unlike a regular commercial bank, it had the federal government as a partner and number one customer. The Bank served as the fiscal agent for the government, holding government tax receipts, paying government bills, performing various financial housekeeping tasks. In return, the government kept its cash as deposits with the First Bank of the United States, giving it a huge financial base. The First Bank’s federal charter, moreover, allowed it to operate branches in all states, giving it a big competitive edge over regular state-chartered banks, which could operate only in the states that chartered them. Gradually the First Bank of the United States evolved into a sort of banker’s bank, gaining the power to police lesser commercial banks.

问答题 Practice 5　　It is obvious today that America has defaulted on this promissory note insofar as her citizens of color are concerned. Instead of honoring this sacred obligation, America has given the Negro people a bad check; a check which has come back marked “insufficient funds.” But we refuse to believe that the bank of justice is bankrupt. We refuse to believe that there are insufficient funds in the great vaults of opportunity of this nation. So we have come to cash this check—a  check that will give US upon demand the riches of freedom and the security of justice.　　We have also come to this hallowed spot to remind America of the fierce urgency of now. This is no time to engage in the luxury of cooling off or to take the tranquilizing drug of gradualism. Now is the time to make real the promises of democracy. Now is the time to rise from the dark and desolate valley of segregation to the sunlit path  of racial justice. Now is the time to open the doors of opportunity to all of God's children. Now is the time to lift our nation from the quick sands of racial injustice to the solid rock of brotherhood. ( I have a dream—Martin Luther King, Jr.）

问答题 Practice 1　　Are organically grown foods the best food choices? The advantages claimed for such foods over conventionally grown and marketed food products are now being debated. Advocates of organic foods—a term whose meaning varies greatly—frequently proclaim that such products are safer and more nutritious than others. The growing interest of consumers in the safety and nutritional quality of the typical North American diet is a welcome development.　　However, much of this interest has been sparked by sweeping claims that the food supply is unsafe or inadequate in meeting nutritional needs. Although most of these claims are not supported by scientific evidence, the preponderance of written material advancing such claims makes it difficult for the general public to separate fact from fiction. As a result, claims that eating a diet consisting entirely of organically grown foods prevents or cures disease or provides other benefits to health have become widely publicized and form the basis for folklore.

问答题 Practice 6　　Yet just as we are beginning to recognize the tremendous diversity of life in these areas, along with the potential benefits newly found species may hold for human society in the form of potential food products and new medicines, they are at risk of being lost forever. With enhanced ability both to identify where these species-rich areas are located and to trawl in deeper water than before, commercial fishing vessels are now beginning to reach down with nets the size of football fields, catching everything in their path while simultaneously crushing fragile corals and breaking up the delicate structure of reefs and seamounts that provide critical habitat to the countless species of fish and other marine life that inhabit the deep ocean floor.　　Because deep sea bottom trawling is a recent phenomenon, the damage that has been done is still limited. If steps are taken quickly to prevent this kind of destructive activity from occurring on the high seas, the benefits both to the marine environment and to future generations are incalculable. And they far outweigh the short-term costs to the fishing industry.

问答题 Practice 2　　Today monocultures have increased dramatically worldwide, mainly through the geographical expansion of land devoted to single crops and year-to-year production of the same crop species on the same land. Available data indicate that the amount of crop diversity per unit of arable land has decreased and that croplands have shown a tendency toward concentration. There are political and economic forces influencing the trend to devote large areas to monoculture, and in fact such systems are rewarded by economies of scale and contribute significantly to the ability of national agricultures to serve international markets.　　The technologies allowing the shift toward monoculture were mechanization, the improvement of crop varieties, and the development of agrochemicals to fertilize crops and control weeds and pests. Government commodity policies these past several decades encouraged the acceptance and utilization of these technologies. As a result, farms today are fewer, larger, more specialized and more capital-intensive. At the regional level, increases in monoculture farming meant that the whole agricultural support infrastructure (i.e. research, extension, suppliers, storage, transport, markets, etc.) has become more specialized.