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Mary evidently is the most diligent student among us.
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第一篇 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. The word "fraction" in the second paragraph means
Obviously these people can be relied on in a crisis.
People are indulging in an illusion whenever they find themselves explaining at a cocktail (鸡尾酒) party, say, that they are "in computers," or "in telecommunications," or "in electronic funds transfer". The implication is that they are part of the high-tech world. Just between US, they usually aren’t. The researchers who made fundamental breakthroughs in those areas are in a high-tech business. The rest of us are (71) of their work. We use computers and other new technology components to develop our products or to organize our affairs. Because we go about this work in teams and projects and other tightly knit working groups(紧密联系在一起的工作小组), we are mostly in the human communication business. Our successes stem from good human interactions by all participants in the effort, and our failures stem from poor human interactions.The main reason we tend to focus on the (72) rather than the human side of the work is not because it’s more (73) , but because it’s easier to do. Getting the new disk drive installed is positively trivial compared to figuring out why Horace is in a blue funk (恐惧) or why Susan is dissatisfied with the company after only a few months. Human interactions are complicated and never very crisp (干脆的, 干净利落的) and clean in their effects, but they matter more than any other aspect of the work.If you find yourself concentrating on the (74) rather than the (75) , you’re like the vaudeville character (杂耍人物) who loses his keys on a dark street and looks for them on the adjacent street because, as he explains, "The light is better there!". 75（）
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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