单选题A Uhaphazard/U knowledge of several styles of a language may be worse than useless if we do not know the type of occasion on which each is appropriate or if we do not know when we are sliding from one of another.

单选题Waving received strict training in oil painting these artists paint in a ______ and figurative style.

单选题Although the colonists ______ to some extent with the native Americans, the latter's influence on American culture and language was not extensive.

单选题 "Popular an" has a number of meanings, impossible to define with any precision, which range from folklore to junk. The poles are clear enough, but the middle tends to blur. The Hollywood Western of the 1930's for example, has elements of folklore, but is closer to junk than to high art or folk art. There can be great trash, just as there is bad high arc The musicals of George Gershwin are great popular art, never aspiring to high art. Schubert and Brahms, however, used elements of popular music--folk themes--in works clearly intended as high art. The case of Verdi is a different one: he took a popular genre--bourgeois melodrama set to music (an accurate definition of nineteenth-century opera) and, without altering its fundamental nature, transmuted it into high art. This remains one of the greatest achievements in music, and one that cannot be fully appreciated without recognizing the essential trashiness of the genre. As an example of such a transmutation, consider what Verdi made of the typical political elements of nineteenth-century opera. Generally in the plots of these operas, a hero or heroine--usually portrayed only as an individual, unfettered by class--is caught between the immoral corruption of the aristocracy and the doctrinaire rigidity or secret greed of the leaders of the proletariat. Verdi transforms this naive and unlikely formulation with music of extraordinary energy and rhythmic vitality, music more subtle than it seems at first hearing. There are scenes and arias that still sound like calls to arms and were clearly understood as such when they were first performed. Such pieces lend an immediacy to the otherwise veiled political message of these operas and call up feelings beyond those of the opera itself. or consider Verdi's treatment of character. Before Verdi, there were rarely any characters at all in musical drama, only a series of situations which allowed the singers to express a series of emotional states. Any attempt to find coherent psychological portrayal in these operas is misplaced ingenuity. The only coherence was the singer's vocal technique: when the cast changed, new arias were almost always substituted, generally adapted from other operas. Verdi's characters, on the other hand, have genuine consistency and integrity. Even if, in many cases, the consistency is that of pasteboard melodrama, the integrity of the character is achieved through the music: once he had become established. Verdi did not rewrite his music for different singers or countenance alterations or substitutions of somebody else's arias in one of his operas, as every eighteenth-century composer had done. When he revised an opera, it was only for dramatic economy and effectiveness.

单选题He quickly ______ behind the building to avoid being hurt by the stones thrown in his direction.

单选题Psychologist George Spilich and colleagues at Washington College in Chestertown, Maryland, decided to find out Whether, as many smokers say, smoking helps them to "think and concentrate." Spilich put young non-smokers, active smokers and smokers deprived (被剥夺) of cigarettes through a series of tests. In the first test, each subject (试验对象) sat before a computer screen and pressed a key as soon as he or she recognized a target letter among a grouping of 96. In this simple test, smokers, deprived smokers and nonsmokers performed equally well. The next test was more complex, requiring all to scan sequences of 20 identical letters and respond the instant one of the letters was transformed into a different one. Non-smokers were faster, but under the stimulation of nicotine (尼古丁), active smokers were faster than deprived smokers. In the third test of short-term memory, non-smokers made the fewest errors, but deprived smokers committed fewer errors than active smokers. The fourth test required people to read a passage, then answer questions about it. Non-smokers remembered 19 percent more of the most important information than active smokers, and deprived smokers bested those who had smoked a cigarette just before testing. Active smokers tended not only to have poorer memories but also had trouble separating important information from insignificant details. "As our tests became more complex," sums up Spilich, "non-smokers performed better than smokers by wider and wider margins." He predicts, "smokers might perform adequately at many jobs until they got complicated. A smoking airline pilot could fly adequately if no problems arose, but if something went wrong, smoking might damage his mental capacity./

单选题The theoretical separation of living, working, traffic and recreation has led to ______.

单选题At dusk, Mr. Hightower would sit in his old armchair in the backyard and {{U}}wistfully{{/U}} lose in reminiscence of his youth romances.

单选题General acceptance of 3-D films may prove hard to Ucome by/U as the experience of three decades ago indicated.

单选题Information technology that helps doctors and patients make decisions has been around for a long time. Crude online tools like WebMD get millions of visitors a day. But Watson is a different beast. According to IBM, it can digest information and make recommendations much more quickly, and more intelligently, than perhaps any machine before it—processing up to 60 million pages of text per second, even when that text is in the form of plain old prose, or what scientists call "natural language. " That's no small thing, because something like 80 percent of all information is "unstructured. " In medicine, it consists of physician notes dictated into medical records, longwinded sentences published in academic journals, and raw numbers stored online by public health departments. At least in theory, Watson can make sense of it all. It can sit in on patient examinations, silently listening. And over time, it can learn and get better at figuring out medical problems and ways of treating them the more it interacts with real cases. Watson even has the ability to convey doubt. When it makes diagnoses and recommends treatments, it usually issues a series of possibilities, each with its own level of confidence attached. Medicine has never before bad a tool quite like this. And at an unofficial coming-out party in Las Vegas last year, during the annual meeting of the Healthcare Information and Management Systems Society, more than 1,000 professionals packed a large hotel conference hall, and an overflow room nearby, to hear a presentation by Marty Kohn, an emergency-room physician and a clinical leader of the IBM team training Watson for health care. Standing before a video screen that dwarfed his large frame, Kohn described in his husky voice how Watson could be a game changer—not just in highly specialized fields like oncology but also in primary care, given that all doctors can make mistakes that lead to costly, sometimes dangerous, treatment errors. Drawing on his own clinical experience and on academic studies, Kohn explained that about one-third of these errors appear to be products of misdiagnosis, one cause of which is "anchoring bias": human beings' tendency to rely too heavily on a single piece of information. This happens all the time in doctors' offices, clinics, and emergency rooms. A physician hears about two or three symptoms, seizes on a diagnosis consistent with those, and subconsciously discounts evidence that points to something else. Or a physician hits upon the right diagnosis, but fails to realize that it's incomplete, and ends up treating just one condition when the patient is, in fact, suffering from several. Tools like Watson are less prone to those failings. As such, Kohn believes, they may eventually become as ubiquitous in doctors' offices as the stethoscope. "Watson fills in for some human limitations," Kohn told me in an interview. "Studies show that humans are good at taking a relatively limited list of possibilities and using that list, but are far less adept at using huge volumes of information. That's where Watson shines; taking a huge list of information and winnowing it down. /

单选题The days when the only fender a businessman needed to stave off a midlife crisis was on the end of a Ferrari are gone.

单选题Greater efforts to increase agricultural production must be made if food shortage ______ avoided.

单选题Professor Jeffrey's lecture on the recycling of waste paper and other garbage will show ______ can still be improved.

单选题He is said to be Uequal/U to any task whatever.

单选题We don't______any difficulties in completing the project so long as we keep within our budget. A. foresee B. fabricate C. infer D. inhibit

单选题Laura, who comes from a wealthy family, spends most of her time enjoying herself, but takes ______ pains with her lessons. A. little B. few C. a little D. a few

单选题The U.S. may so far have enjoyed good luck in escaping a direct SARS hit, but officials aren"t leaving anything to chance. The best hope for averting a SARS epidemic at home will be to keep SARS out at the nation"s borders. Federal immigration laws authorize immigration authorities to exclude non-citizens who are determined to have a "communicable disease of public health significance". Immigration law also authorizes the President by proclamation to suspend the entry of any group of aliens whose entry he deems to be detrimental to the interests of the United States. This little-used power could be deployed to exclude all aliens from affected areas, a policy Taiwan has recently implemented. Under the Public Health Service Act, any individual (citizens included) may be quarantined at an international port of entry if they are reasonably believed to be carrying a designated communicable disease. As of an April 4 Executive Order by President Bush, SARS is now a designated disease. Thus, in tandem with airline screening, federal health authorities are carefully monitoring travelers from affected areas in Asia for SARS symptoms. With an estimated 25,000 individuals entering the country legally from Asia on a daily basis, that is a tall order. A single SARS-infected person getting through the net could bring down the border strategy. The U.S. government might also reinforce the border strategy through restrictions on travel by American citizens to affected areas. In a series of Cold War era decisions, the Supreme Court upheld international travel restrictions for national security reasons, and one can imagine the same rationale applying to a public health emergency. How practical it would be to prohibit—and police—a travel ban to countries such as China is another question. The initial SARS defense, then, hinges on effective border control. But U.S. borders are far from under control. There are an estimated 8～9 million undocumented aliens now in the United States, a figure growing by as many as 500,000 per year. Asia is the largest contributor to undocumented immigration outside the western hemisphere, funneling illegal aliens into the United States through elaborate smuggling networks. SARS could just as easily make serious inroads into the U.S. through this backdoor rather than the front.

单选题From the third paragraph, we can conclude that______.