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Hundreds of buildings were wrecked by the earthquake.
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The chairman proposed that we stop the meeting.
第一篇 Light Night, Dark Stars Thousands of people around the globe step outside to gaze at their night sky. On a clear night, with no clouds, moonlight, or artificial lights to block the view, people can see more than 14,000 stars in the sky, says Dennis Ward, an astronomer (天文学家) with the University Corporation for Atmospheric Research (UCAR) in Boulder, Colo. But when people are surrounded by city lights, he says, they’re lucky to see 150 stars. If you’ve ever driven toward a big city at night and seen its glow from a great distance, you’ve witnessed light pollution. It occurs when light from streetlights, office buildings, signs, and other sources streams into space and illuminates (照亮) the night sky. This haze (薄雾) of light makes many stars invisible to people on Earth. Even at night, big cities like New York glow from light pollution, making stargazing difficult. Dust and particles of pollution from factories and industries worsen the effects of light pollution. "If one city has a lot more light pollution than another," Ward says, "that city will suffer the effects of light pollution on a much greater scale." Hazy skies also make it far more difficult for astronomers to do their jobs. Cities are getting larger. Suburbs are growing in once dark, rural areas. Light from all this new development is increasingly obscuring (使变模糊) the faint (微弱的) light given off by distant stars. And if scientists can’t locate these objects, they can’t learn more about them. Light pollution doesn’t only affect star visibility. It can harm wildlife too. It’s clear that artificial light can attract animals, making them go off course. There’s increasing evidence, for example, that migrating (迁徙) birds use sunsets and sunrises to help find their way, says Sydney Gauthreaux Jr., a scientist at Clemson University in South Carolina. "When light occurs at night," he says, "it has a very disruptive (破坏性的) influence." Sometimes birds fly into lighted towers, high-rises, and cables from radio and television towers. Experts estimate that millions of birds die this way every year. The title "Light Night, Dark Stars" means
第三篇 Water The second most important constituent (构成成份) of the biosphere (生物圈) is liquid water. This can only exist in a very narrow range of temperatures, since water freezes at 0℃ and boils at 100℃. Life as we know it would only be possible on the surface of a planet which had temperatures somewhere within this narrow range. The earth’s supply of water probably remains fairly constant in quantity. The total quantity of water is not known very accurately, but it is about enough to cover the surface of the globe to a depth of about two and three-quarter kilometers. Most of it is in the form of the salt water of the oceans about 97 percent. The rest is fresh, but three quarters of this is in the form of ice at the Poles and on mountains, and cannot be used by living systems until melted. Of the remaining fractional which is somewhat less than one per cent of the whole, there is 10—20 times as much stored underground water as there is actually on the surface. There is also a tiny, but extremely important fraction of the water supply which is present as water vapor in the atmosphere. Water vapor in the atmosphere is the channel through which the whole water circulation (循环) of the biosphere has to pass. Water evaporated (蒸发) from the surface of the oceans, from lakes and rivers and from moist (潮湿的) earth is added to it. From it the water comes out again as rain or snow, falling on either the sea or the land. There is, as might be expected, a more intensive evaporation per unit area over the sea and oceans than over the land, but there is more rainfall over the land than over the oceans, and the balance is restored by the runoff from the land in the form of rivers. Liquid water only exists
One Good Reason to Let Smallpox Live It’s now a fair bet that we will never see the total extinction (灭绝) of the smallpox (天花) virus. When smallpox was completely got rid of in the world, scientists wanted to (51) the killer virus in the last two labs - one in the US and one in Russia. They asked: If smallpox has truly gone from the planet, (52) point was therein keeping these reserves in reality, of course, it was naive to (53) that everyone would let go of such a powerful potential weapon. Undoubtedly several nations still have (54) vials (小药瓶). And the last "official" stocks of live virus bred mistrust of the US and Russia, (55) no obvious gain. Now American researchers have (56) an animal model of the human disease, opening the (57) for tests on new treatments and vaccines (疫苗). So once again there’s a good reason to (58) the virus -just in (59) the disease puts in a reappearance. How do we (60) with the mistrust of the US and Russia (61) . Keep the virus (62) international support in a well-guarded UN laboratory that’s open to all countries. The US will object, of course, just as it (63) a multilateral (多边的) approach to just about everything. But it doesn’t mean the idea is (64) . If the virus is useful, then let’s (65) it the servant of all humanity not just a part of it.
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