四級考試英語專項閱讀題及答案

　　在備考英語四級考試中，堅持每天的英語閱讀練習是考生必做的功課。下面小編為大家帶來四級考試英語專項閱讀題，供考生閱讀練習。

　　四級考試英語專項閱讀題***一***

　　A useful definition of an air pollutantis a compound added directly or indirectly by humans to the atmospherein suchquantities as to affect humans, animals, vegetation, or material adversely ***有害地.. Air pollution requires avery flexibledefinition that permits continuous change. When the first air pollution lawswere established inEngland in the fourteenth century, air pollutants werelimited to compounds that could be seen or smelled—a farcry ***懸殊的差別. from the extensive list of harmful substances known today. Astechnology has developed andknowledge of the health aspects of variouschemicals has increased, the list of air pollutants has lengthened. Inthefuture, even water vapor ***水蒸氣. might be consideredan air pollutant under certain conditions.

　　Many of the more important airpollutants, such as sulfur oxides, carbon monoxide, and nitrogen oxides,arefound in nature. As the Earth developed, the concentrations *** 濃度. of these pollutants were altered byvariouschemical reactions; they became components in biogeochemical ***生物地球化學的. cycles. These serve as an airpurification scheme by allowing thecompounds to move from the air to the water or soil. On a global basis,nature'soutput of these compounds dwarfs that resulting from human activities. However,human productionusually occurs in a localized area, such as a city.

　　In this localized region, human outputmay be dominant and may temporarily overload the natural purificationscheme ofthe cycles. The result is an increased concentration of noxious *** 有害的. chemicals in the air. Theconcentrations atwhich the adverse effects appear will be greater than the concentrations thatthe pollutants wouldhave in the absence of human activities. The actualconcentration need not be large for a substance to be apollutant; in fact thenumerical value tells us little until we know how much of an increase thisrepresents over the concentration that would occur naturally in the area. Forexample, sulfur dioxide has detectable health effects at0.08 parts per million***ppm., which is about 400 times its natural level.Carbon monoxide, however, has a naturallevel of 0.1 ppm and is not usually apollutant until its level reaches about 15 ppm.

　　61、It can be inferred from thefirst paragraph that _________

　　A.water vapor is an air pollutant in localized areas

　　B.the definition of air pollution will continue to change

　　C.a substance becomes an air pollutant only in cities

　　D.most air pollutants today can be seen or smelled

　　62、In what way can naturalpollutants play an important role in controlling air pollution?

　　A.They function as part of a purification process.

　　B.They are dwarfed by the pollutants produced by human activities.

　　C.They are less harmful to living beings than are other pollutants.

　　D.They have existed since the Earth developed.

　　63、According to the passage,the numerical value Of the concentration level of a substance is only useful if

　　A.the other substances in the area are known

　　B.it is a localized area

　　C.it can be calculated quickly

　　D.the naturally occurring level is also known

　　64、Which of the following isbest supported by the passage?

　　A.To effectively control pollution, local government should regularlyrevise the air pollution laws.

　　B.One of the most important steps in preserving natural lands is tobetter enforce air pollution laws.

　　C.Scientists should be consulted in order to establish uniform limitsfor all air pollutants.

　　D.Human activities have great impact on air pollution.

　　65、The passage mainlydiscusses _________

　　A.the economic impact on air pollution

　　B.how much damage air pollutants can cause

　　C.what constitutes an air pollutant

　　D.the quantity of compounds added to the atmosphere

　　四級考試英語專項閱讀題答案

　　BADDB

　　四級考試英語專項閱讀題***二***

　　Is it possible to persuade mankind to livewithout war? War is an ancient institution which has existed for atleast sixthousand years. It was always bad and usually foolish, but in the past thehuman race managed to live withit. Modern ingenuity ***創造力*** has changed this. Either Man will abolishwar, or war will abolish Man. For thepresent, it is nuclear weapons that causethe most serious danger, but bacteriological or chemical weapons, maybeforelong, offer an even greater threat. If we succeed in abolishing nuclearweapons, our work will not be done. Itwill never be done until we havesucceeded in abolishing war. To do this, we need to persuade mankind tolookupon international questions in a new way, not as contests of forec, inwhich the victory goes to the side which ismost skillful in killing people, butby arbitration ***調解. in accordance with agreedprinciples of law. It is not easyto change very old mental habits, but this iswhat must be attempted.

　　There are those who say that the adoptionoft_his or that ideology would prevent war. I believe this to be a bigerror.All ideologies are based on dogmatic *** 教條式的. statements which are, at best, doubtful, and at worst,totallyfalse. Their adherents believe in them fanatically ***狂熱地. that they are willing to go to war in support ofthem.

　　Themovement of world opinion during the past few years has been very largely suchas we can welcome. Ithas become a commonplace *** 老生長談. that nuclear war must be avoided. Of course very difficultproblemsremain in the world, but the spirit in which they are being approachedis a better one than it was some years ago. Ithas begun to be thought, even bythe powerful men who decide whether we shall live or die, that negotiations should reach agreements even if both sides donot find these agreements wholly satisfactory. It has begun to beunderstoodthat the important conflict nowadays is not between different countries, butbetween Man and the atombomb.

　　56、This passage implies thatwar now is _________

　　A.worse than in the past

　　B.as badas in the past

　　C.not so dangerous as in the past

　　D.as necessary as in the past

　　57、In the sentence "To dothis, we need to persuade mankind... "***Line 6, Para.1 ***, "this" refers to _________

　　A.solving international problems

　　B.improving weapons

　　C.abolishing war

　　D.living a peaceful life

　　58、From Paragraph 2 we learnthat the author of the passage

　　A.is a supporter of some modem ideologies

　　B.does not think that the adoption of any ideology could prevent war

　　C.believes that the adoption of some ideologies could prevent war

　　D.has no doubt about the truth of any ideologies

　　59、The last paragraph suggeststhat_________

　　A.international agreements can be reached more easily now

　　B.man begins to realize the danger of nuclear war

　　C.nuclear war will definitely not take place

　　D.world opinion welcomes nuclear war

　　60、According to theauthor,_________.

　　A.war is the only way to solve internatioual disputes

　　B.war will be less dangerous because of the improvement of weapons

　　C.it is impossible for man to live without war

　　D.war must be abolished if man wants to survive

　　四級考試英語專項閱讀題答案

　　ACBAD