题目内容

Pollutants coming from automobile operation have begun to cause many environmental problems. It has been calculated, for example, that 70% of the carbon monoxide, 45% of the nitrogen oxides, and 34% of the hydrocarbon (碳氢化合物) pollution in the United States can be traced directly to automobile exhausts (废气). In addition, rubber, motor oil and other materials accumulate on roadways and are washed into streams, with effects nearly as serious as those of untreated waste water.

In an effort to improve the situation, the U.S. government has made regulations on the use of the constituents (成分) of automobile exhaust gas that are known to cause air pollution. These constituents fall roughly into three types: hydrocarbons that pass through the engine unburned; carbon monoxide, also a product of incomplete burning; and nitrogen oxides which are formed when nitrogen and oxygen are in contact at high temperatures. Besides their own poisonous character, hydrocarbons and nitrogen oxides react in the presence of sunlight to form harmful smog. Carbon monoxide and hydrocarbons are rather easily controlled by the use of higher burning temperatures in engines. Unfortunately, the conditions that produce minimum emission of hydrocarbons tend to raise emission of nitrogen oxides. In a way this difficulty is solved by adding recycled exhaust gas to the fuel mixture, thus avoiding the oversupply of oxygen that favors formation of nitrogen oxides.

California, which has the most strict air-pollution laws in the United States, requires further special compounding of gas to control emissions, and several states have ordered that alcohol be mixed with gas, as this will reduce emissions of the carbon monoxide by 35 per cent and the hydrocarbons by 15 per cent.

67. The author uses figures in Paragraph 1 ________.

     A. to show the consequence of automobile exhausts

     B. to highlight the importance of environment protection

     C. to reflect the rapid growth of automobile use

     D. to criticize the low quality of cars

68. How are nitrogen oxides formed according to the text?

     A. Nitrogen and oxygen are put together in great heat.

     B. Carbon monoxide and oxygen are mixed together.

     C. Hydrocarbons pass through the engine.

     D. Nitrogen is burned incompletely.

69. Which of the following is NOT true according to the text?

     A. Hydrocarbons have no poisonous character themselves.

     B. Smog will form when hydrocarbons meet nitrogen oxides in the sunlight.

     C. Carbon monoxide can be controlled in the engine.

     D. The conditions that decease emission of hydrocarbons will increase emission of nitrogen oxides.

70. According to the text, alcohol is added to gas in order to ______.

     A. increase awareness of environment protection

     B. control air pollution

     C. increase the fuel efficiency

     D. replace gas gradually

AAAB

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It is thought that crying is hardly an activity encouraged by society. Tear, whether they are of sorrow, anger, or joy, typically make Americans feel uncomfortable and embarrassed. The shedder of tears (落泪者) is likely to apologize, even when a great tragedy was the cause. The observer of tears is likely to do everything possible to put an end to the emotional tears. But judging from recent studies of crying behavior, both those responses to tears are often inappropriate and may even be counterproductive (适得其反).

Humans are the only animals clearly known to shed emotional tears. Since evolution has given rise to few purposeless physiological responses, it is logical to assume that crying has one or more functions that enhance (increase) survival.

Although some observers have suggested that crying is a way to ask for assistance form others (as a crying baby might from its mother), the shedding of tears is hardly necessary to get help. Vocal cries would have been quite enough, more likely than tears to gain attention. So, it appears, there must be something special about tears themselves.

Indeed, the new studies suggest that emotional tears may play a direct role in alleviating stress, University of Minnesota researchers who are studying the chemical composition of tears have recently isolated two important chemicals from emotional tears. Both chemicals are found only in tears that are shed in response to emotion. Tears shed because of exposure to cut onion would contain no such substance.

Other researchers are investigating the usefulness of tears as a means of diagnosing human ills and monitoring drugs. At Tulane University’s Teat Analysis Laboratory Dr. Peter Kastl and his colleagues report that they can use tears to detect drug abuse, to study the causes of “dry eye” syndrome（综合症）and the effects of eye surgery, and perhaps even to measure exposure to environmental pollutants.

What does the phrase “both those responses” in Paragraph 1 refer to ?

       A．Crying out of sorrow and shedding tears for happiness.

       B．The embarrassment and unpleasant sensation of the observers.

       C．The tear shedder’s apology and the observer’s effort to stop the crying.

       D．Linking illness with crying and finding the chemical composition of tears.

From the passage we can infer that        .

       A．it is unnatural for people to shed tears

       B．we can reduce our stress by shedding tears

       C．shedders of tears can’t get help by crying loudly

       D．unlike animals, humans can shed tears for survival

What does the passage mainly talk about?

       A．Roles of emotional tears. B．functions of shedding tears.

       C．Unwelcome shedders of tears. D．Research on the effects of tears.

Antarctica and Environment

       Antarctica has actually become a kind of space station – a unique observation post for detecting important changes in the world’s environment. Remote from major sources of pollution and the complex geological and ecological systems that prevail elsewhere, Antarctica makes possible scientific measurements that are often sharper and easier to interpret than those made in other parts of the world.

       Growing numbers of scientists therefore see Antarctica as a distant-early-warning sensor, where potentially dangerous global trends may be spotted before they show up to the north. One promising field of investigation is glaciology. Scholars from the United States, Switzerland, and France are pursuing seven separate but related projects that reflect their concern for the health of the West Antarctic Ice Sheet – a concern they believe the world at large should share.

       The Transantarctic Mountain, some of them more than 14,000 feet high, divide the continent into two very different regions. The part of the continent to the “east” of the mountains is a high plateau covered by an ice sheet nearly two miles thick. “West” of the mountain, the half of the continent south of the Americas is also covered by an ice sheet, but there the ice rests on rock that is mostly well below sea level. If the West Antarctic Ice Sheet disappeared, the western part of the continent would be reduced to a sparse cluster of island.

       While ice and snow are obviously central to many environmental experiments, others focus on the mysterious “dry valley” of Antarctica, valleys that contain little ice or snow even in the depths of winter. Slashed through the mountains of southern Victoria Land, these valleys once held enormous glaciers that descended 9,000 feet from the polar plateau to the Ross Sea. Now the glaciers are gone, perhaps a casualty of the global warming trend during the 10,000 years since the ice age. Even the snow that falls in the dry valleys is blasted out by vicious winds that roars down from the polar plateau to the sea. Left bare are spectacular gorges, rippled fields of sand dunes, clusters of boulders sculptured into fantastic shapes by 100-mile-an-hour winds, and an aura of extraterrestrial desolation.

       Despite the unearthly aspect of the dry valleys, some scientists believe they may carry a message of hope of the verdant parts of the earth. Some scientists believe that in some cases the dry valleys may soak up pollutants faster than pollutants enter them.

What is the best title for this passage?

A Antarctica and environmental Problems.

B Antarctica: Earth’s Early-Warning station.

C Antarctica: a Unique Observation Post.

D Antarctica: a Mysterious Place.

What would the result be if the West Antarctic Ice Sheet disappeared?

A The western part of the continent would be disappeared.

B The western part of the continent would be reduced.

C The western part of the continent would become scattered Islands.

D The western part of the continent would be reduced to a cluster of Islands.

Why are the Dry Valleys left bare?

A Vicious wind blasts the snow away.                B It rarely snows.

C Because of the global warming trend and fierce wind.  D Sand dunes.

Which of the following is true?

A The “Dry Valleys” have nothing left inside.

B The “Dry Valleys” never held glaciers.

C The “Dry Valleys” may carry a message of hope for the verdant.

D The “Dry Valleys” are useless to scientists.

　　For years scientists have been worried about the effects of air pollution on the earth’s natural conditions. Some believe the air inside many houses may be more dangerous than the air outside. It may be one hundred times worse.

　　Indoor air pollution can cause a person to feel tired, to suffer eye-pain, headache and other problems. Some pollutants（ 污染 物） can cause breathing disorders, diseases of blood and even cancer, Most scientists agree that every modern house has some kind of indoor pollution. People began to notice the problem in the early 1970s. It is that when builders began making houses and offices they did not waste energy. To do this they built buildings that limited the flow of air between inside and outside. They also began using manmade building materials. These materials are now known to let out harmful gases. As the problem became more serious, scientists began searching for a way to deal with it. They discovered a natural pollution control system for building— green plants. Scientists do not really know how plants control air pollution. They believe that a plant’s leaves absorb or take in the pollutants. In exchange the plant lets out oxygen through its leaves and through its tiny organizations on its roots. Scientists suggest that all buildings should have one large plant or several small plants inside for every nine square metres of space. Studies of different plants show that each absorbs different chemicals. So the most effective way to clean the air is to use different kinds of plants. Having green plants inside your house can make it a prettier and more healthy place.

　　Generally speaking, indoor air pollution may be more harmful than the air outside because ________.

　　A. the man - made building materials let out dangerous gases inside houses

　　B. there may be more harmful gases outside houses

　　C. the flow of air indoors is limited

　　D. indoor air pollution can make a person seriously ill

　　The most effective way to clean the air is to use different kinds of plants because________.

　　A. they may let out more oxygen which people need

　　B. they can absorb different kinds of the harmful indoor chemicals

　　C. they can take in all kinds of indoor pollutants

        D. they can make your house prettier and more healthy

Cities need to put efforts to deal with pollution and clear the air.

       Chinese cities will need to put efforts to clear up the sky when a new department to improve regional air quality is set up by 2015, according to the latest plan released by the State Council．

       Besides the existing pollution control program for S02, regional emission caps （区域排放上限） for other certain chemicals will be established in the three key air polluting areas— rhe Yangtze River Delta, Pearl River Delta and the Beijing-Tianjin-Hebei region．Coal-consumption caps will also be tried out in some areas, according to the plan．

       The plan is aimed at dealing with regional air pollution—such as acid rain and smog—which have become increasingly obvious in China in recent years and caused a severe threat to people's health, Zhang Lijun, vice-minister of environmental protection, said in an interview on Monday.

       The air quality in a city affects the regions nearby because pollutants （污染物）can travel through the atmosphere, said Chai Fahe, vice-director of Chinese Research Academy of Environmental Sciences．

       “So efforts to reduce air pollution in a single city, targeting a certain pollutant will not oe enough," Chai said．

       Zhang said the country's major industrial districts—the Yangtze River Delta, Pearl River Delta and the Beijing-Tianjin-Hebei region—have recorded more than 100 misty days annually in recent years．

       These three regions, home to at least 200 million people, occupy only 6．3 percent of the country's area but consume 40 percent of the country's coal and produce half of its steel, according to official figures．

       Studies also show that the visibility （能见度） in eastern regions of China has dropped by 7 to 15 km compared to that in the early 1960s, as a result of air pollution．

       Liaoning province, the Shandong Peninsula, Wuhan in Hubei province and its surrounding area, the Changsha-Zhuzhou-Xiangtan region in Hunan province, the Chengdu-Chongqing region, and the western coast of the Taiwan Straits are also listed as areas to carry out such regional air pollution control programs, according to the plan．

       The new plan also requires an improved air quality system, which will measure the pollution levels．"The current system, which only measures some major pollutants, cannot reflect the true picture．" said Chai．

1.It will not be enough to reduce air pollution in a single city because ______.

       A．air pollution has been becoming more and more serious in recent years

       B．air pollution like acid rain and smog is threatening people's health

       C．air pollutants in a city can travel in the sky and affect nearby areas

       D．air pollutants stay in fixed places over the cities

2.Suppose the visibility in eastern regions of China was 130 km in the early 1960s, the visibility there nowadays is            .

       A．123 to 115 km             

       B．137 to 145 km

       C．123 to 145 km                   

       D．115 to 137 km

3.The main purpose of the passage is         .

       A．to inform readers of the damage caused by air pollution

       B．to introduce the new plan to control air pollution

       C．to provide official figures of air pollution levels

       D．to point out the regions affected by air pollution

4.What does the underlined phrase "the true picture" in the last paragraph mean?

       A．The major pollutants．  

       B．The key polluted areas．

       C．The major polluted cities．

       D．The pollution levels．

 

“Everybody in this city wants a car, and I’m no exception. A car brings with it the freedom to travel”, said a friend of mine while reading a car magazine. I might not agree with him, but no doubt he was speaking for a rapidly growing number of middle-class Chinese. While it is true that all the waiting, walking, being part of a crowd, and sweating, are somewhat unpleasant, there are many problems which can arise when our lives rely too much on this invention.

First of all, in terms of polluting the environment, driving a car is the worst act an average person can commit. Beijing now finds itself at the top of the list of the most polluted capital cities in the world with Mexico City in the second place. Research also shows that by 2010 around 90% of total pollutants in Shanghai have come from cars. These pollutions are extremely dangerous to our health. They can damage the lungs, cause cancer, and damage the brain.

Apart from environmental problems, relying too much on cars also creates social problems such as traffic jams, road accidents, and noise pollution. The jeeps that proudly drive through the Hutongs in Beijing as if they are in a race often annoy me, and to make it worse, these drivers seldom respect cyclists.

Of course, we cannot forget the convenience that cars bring us when we need to travel far, but I often find it faster to cycle from one place to another within the city of Beijing, especially with the growing traffic jams.

Since people travel further and more frequently than before, cars will certainly be important in the future. At the same time, however, let us work hard to make sure that this invention brings us a more convenient lifestyle rather than trouble and disease. Let us make good use of cars.

1.What is this passage mainly about?

   A. Environmental problems.

   B. Traffic jams in Beijing.

   C. Problems brought about by cars.

   D. Benefits of using cars.

2. The underlined word commit in Paragraph 2 has the close meaning as ____ .

   A. do something right or legal

   B. do something wrong or illegal

   C. do something good and meaningful

   D. do something bad and meaningless

3.What do we know about the author?

   A. The author doesn’t want a car.

   B. The author agrees that a car offers freedom to travel.

   C. The author suggests that we should rely on bicycles.

   D. The author thinks that the invention of cars leads to many problems.

4.In Paragraph 3, what does the author mean by saying “The jeeps… often annoy me”?

   A. The author is troubled by the way jeeps are driven in the Hutongs of Beijing.

   B. The author thinks that Hutongs are too narrow for jeeps to drive through.

   C. The author thinks that the jeeps are too noisy.

   D. The author is worried that more accidents are caused by jeeps than any other cars.

5.What is the author’s idea in Paragraphs 4 and 5 ?

   A. Cars are only convenient for people traveling far.

   B. We should all give up cars and ride bicycles.

   C. Cars have brought us more convenience than troubles.

   D. We should choose between the car and the bicycle according to the situation.

 

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