单选题The change in that village was miraculous .

单选题The government is debating the education laws.

单选题The change in that village was Umiraculous/U.

单选题Would you please help me fix their watch?A. prepareB. mendC. cleanD. arrange

单选题The economy continued to exhibit signs of decline in September.

单选题Anderson left the table, remarking that he had some work to do.A. sayingB. doubtingC. thinkingD. knowing

单选题Please do not hesitate to {{U}}call{{/U}} me if I can be of further assistance,

单选题Multivitamins Urged for All Pregnant Women A recent study in Tanzania found that when pregnant women took vitamins every day, fewer babies were born too small. Babies that weigh less than two and one-half kilograms at birth have a greater risk of dying. Those that survive are more likely to experience problems with their development. And experts say that as adults they have a higher risk of diseases including heart disease and diabetes. The World Health Organization (WHO) estimates that every year twenty million babies are born with low birth weight. Nine out of ten of them are born in developing countries. The new study took place in Dares Salaam. 4,200 pregnant women received multivitamins. The pills contained all of the vitamins in the B group along with vitamins C and E. They also contained several times more iron and folate than the levels advised for women in developed nations. Pregnant women especially in poor countries may find it difficult to get enough vitamins and minerals from the foods in their diet. The scientists compared the findings with results from a group of 4,000 women who did not receive the vitamins. A report by the scientists, from the United States and Tanzania, appeared in the New England Journal of Medicine . Wafaie Fawzi of the Harvard University School of Public Health led the study. None of the women in the study had HIV, the virus that causes AIDS. The scientists reported earlier that daily multivitamins were a low-cost way to reduce fetal deaths in pregnant women infected with HIV. The earlier work in Tanzania also found improvement in the mothers in their number of blood cells known as lmphocytes. Lymphocytes increase the body"s immunity against infection. The new study in pregnant women who were not infected with the AIDS virus found that multivitamins reduced the risk of low birth weight. Just under eight percent of the babies born to women who took the multivitamins weighed less than 2,500 grams. The rate was almost nine and one-half percent in the group of women who received a placebo, an inactive pill, instead of the vitamins. But the vitamins did not do much to reduce the rates of babies being born too early or dying while still a fetus. Still, the researchers say multivitamins should be considered for all pregnant women in developing countries.

单选题It took me a whole hour to Usolve/U the problem.

单选题Booking in advance is strongly recommended as all daytime tours are subject to demand. Subject to availability, stand -by tickets and tickets for babies without taking a seat can be purchased from the driver. All kinds of tickets must be bought in advance.A. RightB. WrongC. Not mentioned

单选题He replied that this was absolutely impossible.

单选题The explorer lost his way so he climbed to the top of the hill to determine the {{U}}place{{/U}} for himself.

单选题Some Things We Know about Language Many things about language are a mystery, and many will always remain so. But some things we do know. First, we know that all human beings have a language of some sort. There is no race of men anywhere on earth so backward that it has no language, no set of speech sounds by which the people communicate with one another. Furthermore, in historical times, there has never been a race of men without a language. Second, there is no such thing as a primitive language. There are many people whose cultures are undeveloped, who are, as we say, uncivilized, but the languages they speak are not primitive. In all known languages we can see complexities that must have been tens of thousands of years in developing. This has not always been well understood; indeed, the direct contrary has often been stated. Popular ideas of the language of the American Indians will illustrate. Many people have supposed that the Indians communicated in a very primitive system of noises. Study has proved this to be nonsense. There are, or were, hundreds of American Indian languages, and all of them turn out to be very complicated and very old. They are certainly different from the languages that most of us are familiar with, but they are no more primitive than English and Greek. A third thing we know about language is that all languages are perfectly adequate. That is, each one is a perfect means 0f expressing the culture of the people who speak the language. Finally, we know that language changes. It is natural and normal for language to change; the only languages which do not change are the dead ones. This is easy to understand if we look backward in time. Change goes on in all aspects of language. Grammatical features change as do speech sounds, and changes in vocabulary are sometimes very extensive and may occur very rapidly. Vocabulary is the least stable part of any language.

单选题Courageous people think quickly and act without {{U}}hesitation{{/U}}. A. complaint B. consideration C. delay D. anxiety

单选题These programmes are of immense value to old people.

单选题 High Stress May Damage Memory According to a report issued in May 1998, elderly people who consistently high blood levels of the stress hormone. What's more, high levels of cortisol are also associated with shrinking of the hippocampus (海马区), a region of the brain that plays a key role in learning and memory. The findings suggest that even cortisol levels in the normal, "healthy" range can actually accelerate brain aging. The study results "now provide substantial evidence that long-term exposure to adrenal (肾上腺) stress hormones may promote hippocampal aging in normal elderly humans, " write Nada Porter and Phillip Landfield. Cortisol is a hormone releases in response to stress by the adrenal glands(N), which sit on top of the kidneys (肾). Over a 5 to 6 year period, Dr. Sonia Lupine and his colleagues measures 24-hour cortisol levels in 51 healthy volunteers, most of whom were in their 70s. The researchers tested the volunteers' memory on six people in the increasing/high category and five people in the decreasing/moderate group. The groups did not differ in tests of immediate memory, but the increasing/high cortisol group had other memory problems compared with those in the decreasing/moderate group. The researchers also found that the total volume of the hippocampus in those in the increasing/high group was 14% lower than those in the decreasing/moderate group, although there were no differences in other brain regions. The results suggest that "brain aging can be accelerated by levels of adrenal hormones that are not generally regarded as pathological (病态的) and that variation within this normal range is related to variation in the rate of brain aging," write Porter and Landfield. This further suggests that chronic stress may accelerate the worsening of the hippocampus.

单选题 下面有3篇短文，没篇短文后有5道题。请根据短文内容，为每题确定1个最佳选项。{{B}}第一篇{{/B}} {{B}} Pool Watch{{/B}} Swimmers can drown in busy swimming pools when lifeguards fail to notice that they are in trouble. The Royal Society for the Prevention of Accidents says that on average 15 people drown in British pools each year, but many more suffer major injury after getting into difficulties. Now a French company has developed an artificial intelligence system called Poseidon that sounds the alarm when it sees someone in danger of drowning. When a swimmer sinks towards the bottom of the pool, the new system sends an alarm signal to a poolside monitoring station and a lifeguard's pager. In trials at a pool in Ancenis, near Nantes, it saved a life within just a few months, says Alistair McQuade, a spokesman for its maker, Poseidon Technologies. Poseidon keeps watch through a network of underwater and overheard video cameras. Al software analyses the images to work out swimmers' trajectories. To do this reliably, it has to tell the difference between a swimmer and the shadow of someone being east onto the bottom or side of the pool. "The underwater environment is a very dynamic one, with many shadows and reflections dancing around." says McQuade. The software does this by "projecting" a shape in its field of view onto an image of the far wall of the pool. It does the same with an image from another camera viewing the shape from a different angle. If the two projections are in the same position, the shape is identified as a shadow and is ignored. But if they are different, the shape is a swimmer and so the system follows its trajectory. To pick out potential drowning victims, anyone in the water who starts to descend slowly is added to the software's "pre-alert" list, says McQuade. Swimmers who then stay immobile on the pool bottom for 5 seconds or more are considered in danger of drowning. Poseidon double-checks that the image really is of a swimmer, not a shadow, by seeing whether it obscures the pool's floor texture when viewed from over-head. If so, it alerts the lifeguard, showing the swimmer's location on a poolside screen. The first full-scale Poseidon system will be officially opened next week at a pool in High Wycombe. Buckinghamshire. One man who is impressed with the idea is Travor Baylis, inventor of the clockwork radio. Baylis runs a company that installs swimming pools—and he was once an underwater escapologist with a circus. "I say full marks to them if this works and can save lives," he says. But he adds that any local authority spending ￡30,000-plus on a Poseidon system ought to be investing similar amounts in teaching children to swim.

单选题Why can't you stop your eternal complaining! A. everlasting B. long C. monotonous D. lengthy

单选题Attitudes to AIDS Now Most people say that the USA is making progress in fighting AIDS,but they don't know there's no cure and strongly disagree that"the AIDS epidemic(流行)is over,"a new survey finds. The findings, released Thursday by the Kaiser Family Foundation, reassure activists who have worried that public concern about AIDS might disappear in light of recent news about advances in treatment and declines in deaths. "While people are very optimistic about the advances, they' re still realistic about the fact that there is no cure",says Sophia Chang,director of HIV programs at the foundation. The Kaiser survey,like a recent USA TODAY Gallup Poll(民意测验),does find that the number of people ranking AIDS as the country's top health problem has fallen. In the Kaiser poll,38% say it's the top concern,down from 44% in a 1996 poll;in the Oallup Poll, 29% say AIDS is No. 1,down from 41%in 1992 and 67% in 1987. Other findings from Kaiser, which polled more than 1,200 adults in September and October and asked additional questions of another 1,000 adults in November: 52% say the country is making progress against AIDS,up from 32% in 1995. 51% say the government spends too little on AIDS. 86% correctly say AIDS drugs can now lengthen lives; an equal number correctly say that the drugs are not cures. 67% incorrectly say that AIDS deaths increased or stayed the same in the past year;24% know deaths fell. Daniel Zingale,director of AIDS Action Council,says,"I'm encouraged that the American people are getting the message that the AIDS epidemic isn't over. I hope the decision-makers in Washington are getting the same message... We have seen signs of complacency(得意). /

单选题Regular visits from a social worker can be of immense value to old people living alone.