请教费费135－133

isabellu

Nature constantly adjusts the atmospheric carbon level. An increase in the level causes the atmosphere to hold more heat, which causes more water to evaporate from the oceans, which causes increased rain. Rain washes some carbon from the air into the oceans, where it eventually becomes part of the seabed. A decrease in atmosphere carbon causes decreased evaporation from the oceans, which cause less rain, and thus less carbon is washed into the oceans. Yet some environmentalists worry that burning fossil fuels may raise atmospheric carbon to a dangerous level. It is true that a sustained increase would threaten human life. But the environmentalists should relax---nature will continually adjust the carbon level.
133. Which one of the following, if true, would most weaken the argument in the passage?
(A) Plant life cannot survive without atmospheric carbon.
(B) It is not clear that breathing excess carbon in the atmosphere will have a negative effect on human life.
(C) Carbon is part of the chemical “blanket” that keeps the Earth warm enough to sustain human life.
(D) Breathing by animals releases almost 30 times as much carbon as does the burning of fossil fuels.
(E) The natural adjustment process, which occurs over millions of years, allow wide fluctuations in the carbon level in the short term.
E 我怎么觉得这个是strengthen不是weaken阿？要是改成do not allow就明白了

[此贴子已经被作者于2004-3-3 12:28:25编辑过]

dansy

题干先说大自然能自己调节atmospheric carbon level (ACL)， 然后说了一堆连环效应。然后话锋一转说有些人不同意这样的说法，而觉得ACL有时还是到了有害的地步。然后话锋又一转，说这些人太多虑了，言下之意还是同意大自然能自然调节ACL。题目问反驳，应该反驳的是“大自然能自然调节ACL”。 答案E中说在短期内ACL有巨大变化，可以理解成就算你大自然能调节，但是那是长期作用，短期能变化巨大，有可能ACL达到有害水平噢！有削弱作用。其实A无关，BCD无关，顶多是变相支持。

weiyu

Nature constantly adjusts the atmospheric carbon level. An increase in the level causes the atmosphere to hold more heat, which causes more water to evaporate from the oceans, which causes increased rain. Rain washes some carbon from the air into the oceans, where it eventually becomes part of the seabed. A decrease in atmosphere carbon causes decreased evaporation from the oceans, which cause less rain, and thus less carbon is washed into the oceans (Self-adjustment principle). Yet some environmentalists worry that burning fossil fuels may raise atmospheric carbon to a dangerous level. It is true that a sustained increase would threaten human life. But the environmentalists should relax---nature will continually adjust the carbon level.
Conclusion:That a sustained increase would threaten human life is not right Because nature will continually adjust the carbon level
ChoiceE: The natural adjustment process, which occurs over millions of years, allow wide fluctuations in the carbon level in the short term. Thus the fluctuation might bring about an unexpected high desity of CO2, such short-term increase may threten human life.