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摘要:Questions 61-65 are based on the following passage. 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 adverse

 Questions 61-65 are based on the following passage.

  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 (悬殊的差别. 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 (水蒸气. 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 ( 浓度. of these pollutants were altered byvariouschemical reactions; they became components in biogeochemical (生物地球化学的. 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


   61-65 BADDB

There are people in Italy who can’t stand soccer. Not all Canadians love hockey. A similar situation exists in America, where there are those individuals you may be one of them who yawn or even frown when somebody mentions baseball. 『Baseball to them means boring hours watching grown men in funny tight outfits standing around in a field staring away while very little of anything happens.』① They tell you it’s a game better suited to the 19th century, slow, quiet, gentlemanly. These are the same people you may be one of them who love football because there’s the sport that glorifies “the hit”.By contrast, baseball seems abstract, cool, silent, still.

  On TV the game is fractured into a dozen perspectives, replays, close?ups. The geometry of the game, however, is essential to understanding it. You will contemplate the game from one point as a painter does his subject; you may, of course, project yourself into the game. It is in this projection that the game affords so much space and time for involvement. The TV won’t do it for you.

  Take, for example, the third baseman. You sit behind the third base dugout and you watch him watching home plate. His legs are apart, knees flexed. His arms hang loose. He does a lot of this. The skeptic still cannot think of any other sports so still, so passive. 『But watch what happens every time the pitcher throws: the third baseman goes up on his toes, flexes his arms or bring the glove to a point in front of him, takes a step right or left, backward or forward, perhaps he glances across the field to check his first baseman’s position.』② Suppose the pitch is a ball. “Nothing happened,” you say. “I could have had my eyes closed.”

  The skeptic and the innocent must play the game. And this involvement in the stands is no more intellectual than listening to music is. Watch the third baseman. Smooth the dirt in front of you with one foot; smooth the pocket in your glove; watch the eyes of the batter, the speed of the bat, the sound of horsehide on wood. If football is a symphony of movement and theatre, baseball is chamber music, a spacious interlocking of notes, chores and responses.

  1. The passage is mainly concerned with ______.

  A. the different tastes of people for sports

  B. the different characteristics of sports

  C. the attraction of football

  D. the attraction of baseball

  2. Those who don’t like baseball may complain that ______.

  A. it is only to the taste of the old

  B. it involves fewer players than football

  C. it is not exciting enough

  D. it is pretentious and looks funny

  3. The author admits that ______.

  A. baseball is too peaceful for the young

  B. baseball may seem boring when watched on TV

  C. football is more attracting than baseball

  D. baseball is more interesting than football

  4. By stating “I could have had my eyes closed. ” the author means (4th paragraph last sentence):

  A. The third baseman would rather sleep than play the game.

  B. Even if the third baseman closed his eyes a moment ago, it could make no different to the result.

  C. The third baseman is so good at baseball that he could finish the game with eyes closed all the time and do his work well.

  D. The consequent was too bad he could not bear to see it.

  5. We can safely conclude that the author ______.

  A. likes football B. hates football

  C. hates baseball D. likes baseball


  1. D 主旨题。文章第一段简述了人们对垒球所持的偏见——认为它毫无活力、从容和缓,不像橄榄球那样(禁止)迭起、令人激动。文章的第二、三、四、五段探讨了垒球的根本特征及欣赏角度,文章的最后一句话用一个比喻概括了垒球的魅力:“如果橄榄球是一曲交响乐的话,那么,垒球中所表现出来的运动恰似一曲优美的室内乐。”可见,本文主要探讨的是垒球的特点及其欣赏。

  2. C 细节题。文章第一段指出:许多人不喜欢垒球,一提起垒球这些人就打哈欠甚至皱眉头。对他们来说,看垒球意味着眼巴巴地观望着身着运动装(outfit)的人呆立在球场上,东瞧瞧西望望,很少有什么(激动人心的)事发生——没意思透了。他们认为这样的运动更适合上个世纪的人的口味,不像橄榄球那样充满活力。

  3. B 推断题。第三段指出,在电视上,垒球运动被切换成不同角度的画面,而且不断地使用重放、特写等电视制作技术,这破坏了该运动的整体运动感,使观众无法将自己投入(project)到运动中去,以体会到这种寓动于静的运动之美。电视做不到这一点(The TV won’t do it for you),因此,电视上的垒球比赛看上去(seems)孤孤单单、冷冷清清、沉沉静静、慢慢腾腾。C、D不对,作者仅指出了不同运动有不同运动的特征,并未说哪种运动优于哪种。

  4. B 推断题。第四段整个都在描述垒球场上的一个场景:拿三垒的运动员假设对方全投出好球,作好了一切准备,但是对方投出的并不是好球。所以在那时候他的准备做不做都不会影响比赛结果。他说本来可以闭上眼睛,意思就是B项所写的。

  5. D 推断题。在本文中,作者主要探讨了垒球的特征及欣赏,作者着重指出的是:只有根据垒球的特征来欣赏它,才能体会到它的魅力。在他看来,观察到垒球比赛中运动员的各种动作、垒球位之间的关系等是欣赏它的关键(第三段第二句)。只有从整体来把握它,才能看到每一个小的动作、每一个眼神乃至于“静止”的意义,也只有这样,才能全身心地投入比赛中,欣赏到它的魅力。可见,作者对垒球有很深的理解而且非常喜爱垒球。



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