Question

阅读理解 　　It was once thought that air pollution affected only the area immediately around large cities with factories or heavy automobile traffic．Today, we know that although these are the areas with the worst air pollution, the problem is literally worldwide．On several occasions over the past decade, a heavy cloud of air pollution has covered the entire eastern half of the United States and led to health warning even in rural areas away from any major concentration of manufacturing and automobile traffic．In fact, the very climate of the entire earth may be affected by air pollution．Some scientists feel that the increasing concentration of carbon dioxide in the air resulting from the burning of fossil fuels(coal and oil)is creating a “greenhouse effect” holding in heat reflected from the earth and raising the world's average temperature．If this view is correct and the world's temperature is raised only a few degrees, much of the polar ice cap will melt and cities such as New York, Boston, Miami, and New Orleans will be under water． 　　Another view, less widely held, is that increasing particulate matter in the atmosphere is blocking sunlight and lowering the earth's temperature－a result that would be equally disastrous．A drop of just a few degrees could create something close to new ice age and would make agriculture difficult or impossible in many of our top farming areas．At present we do not know for sure that either of these conditions will happen(though one recent government report prepared by experts in the field concluded that the greenhouse effect is very likely)．Perhaps, if we are very lucky, the two tendencies will offset each other and the world's temperature will stay about the same as it is now． (1) As pointed out at the beginning of the passage, people used to think that air pollution ________． [　　] A． caused widespread damage in the countryside B． affected the entire eastern half of the United States C． had damaging effects on health D． existed just in urban and industrial areas (2) As far as the greenhouse effect is concerned, the author ________． [　　] A． shares the same view with the scientists B． is uncertain of its occurrence C． rejects it as being rootless D． thinks that it will destroy the world soon (3) The world “offset”(the last sentence)could best be replaced by ________． [　　] A． burn down B． set up C． make up for D． catch up with (4) We can learn from the passage that ________． [　　] A． raising the world's temperature a few degrees would not do harm to life on earth B． lowering the world's temperature only a few degrees would lead many major farming areas to disaster C． the author believes that the world's temperature will remain constant in the years to come D． the concentration of carbon dioxide would certainly block sunlight (5) This passage is primarily concerned with ________． [　　] A． the greenhouse effect B． the burning of fossil fuels C． the possible effect of air pollution D． the probability of a new ice age

Answer 1

答案：1．D;2．B;3．C;4．B;5．C;
解析：

(1)	本题考查细节理解。根据第一段开头一句可知人们过去曾经认为空气污染只发生在都市和工业区。
(2)	本题考查作者态度。根据第二段中的“At present we do not know for sure that either of these conditions will happen．”可知作者不确定两种观点中的任何一种,自然也不确定温室效应的存在。
(3)	本题考查猜测词义。一种观点认为地球温度会上升，另一种观点认为地球温度会降低，因此如果二者互相“弥补”，地球温度可能会保持目前的状态。
(4)	本题考查细节理解。根据第二段第二句可判断此项正确。第二段最后部分是说假如非常幸运，地球的温度将保持现状，但这只是假设，所以C项错误。
(5)	[解析]本题考查主旨大意。两种观点都能自圆其说，所以选择此项。其余三项都是其中一种观点中涉及到的内容，不具有概括性。 　　[文章大意]空气污染究竟会导致什么样的后果?有人认为冰川将会融化，有人则认为世界将变成冰川，孰是孰非?难以预料。也许最好的结局是二者能够互相中和。