Questions56-60are based on the following passage.
It was once thought that air pollution affected only the area immediately around large cities with factories and 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 warnings
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 agreenhouse effect一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 Y0rk,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.
56、According to the passage,people today think that air pollution________.
A.exists merely in urban and industrial areas
B.may have an effect on the entire earth
C.causes widespread damage in the countryside
D.is not so serious as it used to be
57、Thegreenhouse effectresults from________.
A.the concentration of carbon dioxide in the air
B.the increasing particulate matter in the atmosphere
C.the burning of firewood
D.the blocking of sunlight
58、What does the author think of the possibility of a new ice age?
A.He rejects it as being ungrounded.
B.He holds the same view.
C.He is uncertain of its occurrence.
D.He thinks that would happen soon.
59、The wordoffset Line 3,Para.4.means________.
A.slip into
B.catch up with
C.set up
D.make up for
60、The passage is mainly about__________.
A.the potential effect of air pollution
B.the possibility of a new ice age
C.the effects of global warming
D.the causes of climate change
答案解析:
56-60 BACDA
以上就是查字典大学网为同学们带来的“2016年12月大学英语四级阅读暑期练习及答案(三十一)”内容了,希望看完能够带给大家一些力量,对同学的生活有所启示,更多内容在这里,请继续关注我们。
成功的起点是相信,成功的速度是执行,成功的过程是坚持
自信来源于成功的暗示,自卑来源于失败的暗示
富兰克林另类励志语录
莎士比亚口中的励志语录
柳传志创业心得语录5条
天注定,那是“命”;但你可以决定怎么面对,那是“运”
无论苦难或成功都是对我们的考验
人生的成就,取决于你生命的最后一步
成功没有捷径,为“最好的自己”加油
李嘉诚励志语录:理想的路总为有信心的人预备
耶鲁大学励志语录:敢于尝试,敢于丢脸
损失变商机
给自己一个成功的理由,你的路就会越走越宽
人生路上,走过的昨天,脚下的今天,面前的明天,都只有相对的意义
第一流的人做第一流的事,永远不要和老鼠比赛
人生平均只有7次决定人生走向的机会,你抓到了吗?
大事业往往要从小事情一步步做起来
乌有的木头