[单项选择]There would be no air pollution to this city because ______.
A. there was a special plant to treat the polluted air
B. the city was away from the mainland
C. people in the city did not burn oil or coal
D. vehicles there were powered by electricity

[单项选择]There would be no air pollution to this city because ______.
A. there was a special plant to treat the polluted air
B. the city was away from the mainland
C. people in the city did not burn oil or coal
D. vehicles there were powered by electricity

[单项选择]An energy tax would curb ordinary air pollution, limit oil imports and cut the budget ______
A. disposition
B. discrepancy
C. defect
D. deficit

[单项选择]______ the heavy pollution, the city officials have decided to cancel school for the day.
A. Prior
B. By means of
C. Due to
D. Through

[单项选择]Jack thought he would find the office easily because ______.

[单项选择]（）no gravity,there would be no air around the earth,hence no life.
A. If there was
B. If there had been
C. Were there
D. Had there been

[单项选择]（） no gravity, there would be no air around the earth.
A. Were there
B. Was there
C. There were
D. There be.

[单项选择]（）no gravity, there would be no air around the earth. heace no life.
A. If there had been
B. If there was
C. Had there been
D. Were there

[单项选择]George went to the air force training school because he wanted ______.
A. to fight the war
B. to fly
C. to he a pilot
D. to be a passenger

[单项选择]George went to the air torte training school because he wanted ______.
A. to fight the war
B. to fly
C. to be pilot
D. to be a passenger

[单项选择]Who is hurt by air pollution


A. The buyer.
B. The seller.
C. Both the buyer and the seller.
D. None.

[单项选择]

Passage Five
Scientists claim that air pollution causes a decline in the world’ s average air temperature. In order to prove that theory, ecologists have turned to historical data in relation to especially huge volcanic eruptions. They suspect that volcanoes effect weather changes that are similar to air pollution.
One source of information is the effect of the eruption of Tambora, a volcano in Sumbawa, the Dutch East Indies ( the former name of the Republic of Indonesia) ,in April 1815. The largest recorded volcanic eruption, Tambora threw 150 million ton of fine ash into the stratosphere. The ash from a volcano spreads worldwide in a few days and remains in the air for years. Its effect is to turn in coming solar radiation into space and thus cool the earth. For example, records of weather in Eng land show that between April and November 1815, the average temperature had fallen 4.5°F during the next twenty-four months, England suffered one of th
A. there was a long interval between cause and effect
B. the weather was difficult for us to forecast
C. weather forecasts were inaccurate
D. ecologists didn't exist until modem times