单选题Every other week, new studies appear that either criticize or praise the roasted bean. Are there grounds for concern under the fragrant foam? Some people believe that coffee bean can lower the incidence of some diseases. First, the disease is diabetes. A study of 14,000 people in Finland which is the world's greatest per-capita consumer of coffee found that women who drank three to four cups a day cut their risk of developing diabetes by 29 percent. For men, it was 27 percent. Researchers aren't sure why, but suspect that the antioxidants in coffee help deliver insulin to the body's tissues. Second, it can lower cancer. In Japan, a study of 90,000 people revealed those who drank coffee every day for ten years were half as likely to get liver cancer. Meanwhile, German scientists have identified an active compound in coffee that boosts enzymes thought to prevent colon cancer. Finally, it can also lower Parkinson's disease. Researchers in Hawaii monitored the health of more than 8,000 Japanese-American men for 30 years and discovered that those who drank a cup of coffee a day had less than half the incidence of Parkinson's disease. A possible clue as to why. caffeine promotes the release of dopamine, a substance involved with movement and usually consumed in Parkinson's sufferers. On the contrary, there's hot debate on whether drinking coffee is a cardiac risk. A Greek study of more than 3,000 people found coffee drinkers has higher levels of bad substances in their blood than non-drinkers. But Harvard researchers looking at the health of coffee drinkers over 20 years could not localize any extra coronary problems. Nevertheless, a study of 2,028 Costa Ricans found those with a gene variant that processes caffeine four times slower than average, and who also drank two to three cups of coffee a day, upped their heart-attack risk by 36 percent. As this group me-tabolises caffeine slower, it remains in the body for longer -- possibly pushing up blood pressure. For most of us, the humble cup of coffee is simply a harmless and enjoyable way to kick -- start the day or give us an excuse for some time out. No more, no less. However, it is important to remember that different people exhibit different tolerance levels to caffeine -- it is, after all, a drug.

单选题 I remember the way the light touched her hair. She turned her head, and our eyes met, a momentary awareness in that raucous fifth grade classroom. I felt as though I' d been struck a blow under the heart. Thus began my first love affair. Her name was Rachel, and I mooned my way through the grade and high school, stricken at the mere sight of her, tongue-tied in her presence. Does anyone, anymore, linger in the shadows of evening, drawn by the pale light of a window—her window—like some hapless summer insect? That delirious swooning, asexual but urgent and obsessive, that made me awkward and my voice crack, is like some impossible dream now. I would catch sight of her, walking down an aisle of trees to or from school, and I' d become paralyzed. She always seemed so poised, so self-possessed. At home, I' d relive each encounter, writhing at the thought of my inadequacies. We eventually got acquainted and socialized as we entered our adolescence, she knew I had a case on her, and I sensed her affectionate tolerance for me. "Going steady" implied a maturity we still lacked. Her Orthodox Jewish upbringing and my own Catholic scruples imposed an inhibited grace that made even kissing a distant prospect, however fervently desired. I managed to hold her once at a dance-chaperoned, of course. Our embrace made her giggle, a sound so trusting that I hated myself for what I'd been thinking. At any rate, my love for Rachel remained unrequited. We graduated from high school, she went on to college, and I joined the Army. When World War II engulfed us, I was sent overseas. For a time we corresponded, and her letters were the highlight of those grinding endless years. Once she sent me a snapshot of herself in a bathing suit, which drove me to the wildest of fantasies. I mentioned the possibility of marriage in my next letter, and almost immediately her replies became less frequent, less personal. Her Dear John letter finally caught up with me while I was awaiting discharge. She gently explained the impossibility of a marriage between us. Looking back on it, I must have recovered rather quickly, although for the first few months I believed I didn't want to live. Like Rachel, I found someone else, whom I learned to love with a deep and permanent commitment that has lasted to this day.

单选题For more than two decades, U. S. courts have been limiting affirmative-action programs in universities and other areas. The legal rationale is that racial preferences are unconstitutional, even those intended to compensate for racism or intolerance. For many colleges, this means students can be admitted only on merit, not on their race or ethnicity. It has been a divisive issue across the U. S., as educators blame the prolonged reaction to affirmative-action for declines in minority admissions. Meanwhile, activists continue to battle race preferences in courts from Michigan to North Carolina. Now, chief executives of about two dozen companies have decided to plunge headfirst into this politically unsettled debate. They, together with 36 universities and 7 nonprofitable organizations, formed a forum that set forth an action plan essentially designed to help colleges circumvent court-imposed restrictions on affirmative action. The CEOs" motive. "Our audience is growing more diverse, so the communities we serve benefit if our employees are racially and ethnically diverse as well", says one CEO of a company that owns nine television stations. Among the steps the forum is pushing, finding creative yet legal ways to boost minority enrollment through new admissions policies; promoting admissions decisions that look at more than test scores; and encouraging universities to step up their minority outreach and financial aid. And to counter accusations by critics to challenge these tactics in court, the group says it will give legal assistance to colleges sued for trying them. "Diversity diminished by the court must be made up for in other legitimate, legal ways, " says, a forum member. One of the more controversial methods advocated is the so-called 10% rule. The idea is for public universities—which educate three-quarters of all U. S. undergraduates—to admit students who are in the top 10% of their high school graduating class. Doing so allows colleges to take minorities who excel in average urban schools, even if they wouldn"t have made the cut under the current statewide ranking many universities use.

单选题One of the chief difficulties in accurate earthquake warning is that.

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单选题Swift invented famous ______ in his world famous Gulliver's Travels. A. Lilliput B. Brobdingag C. Celestial city D. Morality Pool

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单选题The author thinks the use of English will get worse in the future because

单选题______ is the author of Scarlet Letter. A. Hawthorne B. Mark Twain C. Melville D. Cooper

单选题The example of a gull chick pecking the parent's bill illustrates that

单选题In the atmosphere, carbon dioxide acts rather like a one-way mirror -- the glass in the roof of a greenhouse which allows the sun's rays to enter but prevents the heat from escaping. According to a weather expert's prediction, the atmosphere will be 3~C warmer in the year 2050 than it is today, if man continues to burn fuels at the present rate. If this warming up took place, the ice caps in the poles would begin to melt, thus raising sea level several metres and severely flooding coastal cities. Also, the increase in atmospheric temperature would lead to great changes in the climate of the northern hemisphere, possibly resulting in an alteration of the earth's chief food-growing zones. In the past, concern about a man-made warming of the earth has concentrated on the Arctic because the Antarctic is much colder and has a much thicker ice sheet. But the weather experts are now paying more attention to West Antarctic, which may be affected by only a few degrees of warming: in other words, by a warming on the scale that will possibly take place in the next fifty years from the burning of fuels. Satellite pictures show that large areas of Antarctic ice are .already disappearing. The evidence available suggests that a warming has taken place. This fits the theory that carbon dioxide warms the earth. However, most of the fuel is burnt in the northern hemisphere, where temperatures seem to be falling. Scientists conclude, therefore, that up to now natural influences on the weather have exceeded those caused by man. The question is: Which natural cause has most effect on the weather? One possibility is the variable behavior of the sun. Astronomers at one research station have studied the hot spots and "cold" spots (that is, the relatively less hot spots) on the sun. As the sun rotates, every 27.5 days, it presents hotter or "colder" faces to the earth, and different aspects to different parts of the earth. This seems to have a considerable effect on the distribution of the earth's atmospheric pressure, and consequently on wind circulation. The sun is also variable over a long term: its heat output goes up and down in cycles, the latest trend being downward. Scientists are now finding mutual relation between models of solar-weather interactions and the actual climate over many thousands of years, including the last Ice Age. The problem is that the models are predicting that the world should be entering a new Ice Age and it is not. One way of solving this theoretical difficulty is to assume a delay of thousands of years while the solar effects overcome the inertia of the earth's climate. If this is right, the warming effect of carbon dioxide might thus be serving as a useful counter-balance to the sun's diminishing heat.

单选题In 1942, the HMS Edinburgh was sunk in the Barents Sea. It was on its 1 back to Britain with ninety-one boxes of Russian gold. 2 thirty-nine years it lay there, too deep for divers to 3 . No one was allowed to explode it, either, since the bodies of sixty of the crew also lay in the 4 . Then, in 1981, an ex-diver called Jessop decided to try using new diving techniques. 5 he could not afford to finance the 6 which was going to cost four million pounds, he had to look for people who were 7 to take the risk. 8 , they were not even sure the gold was going to be there! First a Scottish diving company, then a German shipping company agreed to join in the retrieval 9 . Not long after that, Jessop 10 a fourth company to take a 11 . Since the gold was the 12 of the British and the Soviet governments, they both hoped to make a 13 , too! The biggest problem was how to get. 14 the gold. Fortunately, they were able to examine the Edinburgh"s sister ship, the HMS Belfast , to 15 out the exact location of the bomb room, 16 the gold was stored. They knew it was to be an extremely difficult and dangerous undertaking. To reach the gold, they would have to cut a large square 17 the body of the ship, go through the empty fuel tank and down to the bomb room. After twenty-eight dives, they 18 to find the first bar. Everyone worked 19 the clock, helping to clean and stack the gold, 20 as to finish the job as quickly as possible.

单选题According to the passage, which of the following is NOT true of women in pattern III families?