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[主观题]

Water pollution can't affect nature's balance in oceans, lakes and rivers.A．YB．NC．NG

Water pollution can't affect nature's balance in oceans, lakes and rivers.

A．Y

B．N

C．NG

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发布时间：2021-05-29

更多“Water pollution can't affect nature's balance in oceans, lakes and rivers.A．YB．NC．NG”相关的问题

第1题

Water pollution can't affect nature's balance in oceans, rakes and rivers.A．YB．NC．NG

Water pollution can't affect nature's balance in oceans, rakes and rivers.

A．Y

B．N

C．NG

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第2题

Noise pollution is not a necessary price to pay for living in an industrial society. Much

can be done to reduce the severity of the problem. For example, vehicles and other machines can be built to produce less noise. Four-cycle engines can replace much noisier two-cycle engines in such products as lawnmowers, motorboats, and jet skis. Labels that indicate the noise levels of appliances and tools can help consumers avoid noisy products and choose quieter alternatives.

Even after noise is generated, steps can be taken to reduce human exposure to it. At homes or in offices, insulation of walls and double-glazing of windows can decrease sound from traffic, neighbors, and other sources from the outside world. Sound walls along highways can shield nearby neighborhoods from traffic noise. Individuals should protect themselves with earplugs or ear protectors, particularly when noise levels exceed 85 decibels (分贝).

In the industrialized nations, governments have laws and policies to counter noise pollution. In the United States, at least six federal agencies are involved in controlling noise pollution. Since 1969 the Federal Aviation Administration (FAA) has monitored and controlled noise from airplanes, The agency requires that new aircraft meet specified noise standards and that old ones be retrofitted (翻新) or retired. Local airport authorities, with FAA approval, reduce the impacts of noise pollution by routing flights over water or unpopulated areas on takeoff and landing, and by limiting traffic at night. The FAA also encourages airports and local governments to take steps on the ground, such as constructing sound barriers, insulating buildings, and restricting residential development in noisy areas. In extreme eases, airports have relocated people living under flight paths.

In the last 30 years, the United States and other countries have expended considerable efforts to control noise pollution. Most vehicles and many other noise producers are quieter than they used to be. On the other hand, there are more noise-making machines than ever, operating mare of the time. In the United States, most of the roles governing noise pollution were established at least two decades ago, and critics are calling for new, stronger measures, as well as for better enforcement of the old ones. What is true of most other kinds of pollution is also true of noise: Our best efforts against it tend merely to keep matters from getting dramatically worse.

The first paragraph tries to tell us how to control noise pollution by ______.

A．taking measures to reduce human exposure to noise

B．using or replacing with quieter products

C．appealing to Government to set up laws

D．people's serf consciousness

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第3题

Obviously, nuclear power can never be the only （solve) ________ to energy crisis.27.

Obviously, nuclear power can never be the only (solve) ________ to energy crisis.

27. It was in his childhood that he read most of the books (write) ________ by Mark Twain.

28. Nobody at the meeting would (belief) ________ that the new proposal could be carried out smoothly.

29.If the rent is as much as $750 a month, water, gas and electricity should (include) ________.

30. The lecture was so (bore)________ that many classroom fell asleep.

31. Mr. Smith considered (sell) ________ his car and his house before moving to Beijing.

32. My mother (enjoy) ________ a better health since we came to live in this beautiful seaside city.

33. The government is trying to find a way to deal with the problem of pollution (effective) ________.

34. The young man did not have enough money; otherwise he (buy) ________ a more expensive watch.

35. With the help of the police, the woman finally found her (lose) ________ child after a sleepless night.

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第4题

Questions下列各 are based onthe following passage. A useful definition of an air polluta

ntis 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,naturesoutput 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. 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

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第5题

听力原文： Spaceships travel around the earth, go to the moon, and return home safely. T

he astronauts carry important supplies with them on the spaceship — food, water and air. Sometimes there are problems on the spaceship, and the astronauts have to understand how the spaceship works in order to repair the problems. In a way, all of us are really on a spaceship, the planet Earth. We move around the Sun at 18 miles per second and never stop. On our spaceship we have four billion people and a limited supply of air, water and land. These supplies, just like the limited supplies on the astronauts spaceship, have to be used carefully because we cant buy new air, water or land from anywhere else. Everyone needs air, water and land to live — this is our environment. The environment on our planet is a closed system; nothing new is ever added. Nature recycles its resources. Water, for example, evaporates and rises to form. clouds. This same water returns to the earth as rain or snow. The rain that falls today is actually the same water that fell on the dinosaurs 70 million years ago. Over the years, people have changed the environment. We have poured back into the land, air, and water more wastes than nature can clean. So we have pollution today. To continue to survive, we must learn how to use the Earths resources wisely, without destroying them. To save the spaceship Earth, we must cooperate with nature and learn better ways to use, not to abuse our environment. Questions 20 to 22 are based on the passage you have just heard. 20. Which would be the best title for the passage？ 21. Which is true according to the passage？ 22. What can we conclude from the passage？20．

A．The present population on earth is fourteen billion.

B．Water is recycled every seventy million years.

C．The planet earth travels around the sun at 18 miles per second.

D．The earth is compared to a spaceship because they both travel around the sun.

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第6题

听力原文：Our environment is being polluted faster than nature and man's present efforts ca

听力原文： Our environment is being polluted faster than nature and man's present efforts can prevent it. Time is bringing us more people, and more people will bring us more industry, more motor vehicles, larger cities, and the growing use of man-made materials.

What can explain and solve this problem？ The fact is that pollution is caused by man-by his desire for a modern way of life. We make "increasing industrialization" our chief aim. For its sake, we are willing to sacrifice every thing: clean air, pure water, good food, our health and the future of our children. There is a constant flow of people from the countryside into the cities, eager for the benefits of modern society. But as our technological achievements have grown in the last twenty years, so pollution has be come a serious problem.

Isn't it time we stopped to ask ourselves where we are going and why？ It reminds one of the stories about the airline pilot who told his passengers over the loudspeaker, "I've some good news and some bad news. The good news is that we're making rapid progress at 530 miles per hour. The bad news is that we're lost and don't know where we're going." The sad fact is that this becomes a true story when applied to our modern society.

(30)

A．We are making too many vehicles.

B．We have more and more industry.

C．There are too many developing countries.

D．People use too many man-made materials.

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第7题

Now all countries in the world are faced with the same environmental problems, air polluti

on, water pollution, the loss of species, etc.

A．Y

B．N

C．NG