[单项选择]We are using up our natural resources too quickly and at the same time we are（）our environment with dangerous chemicals.
A. protecting
B. saving
C. polluting
D. fighting

[单项选择]We are using up our natural resources too quickly and at the same time we are ______ our environment with dangerous chemicals.
A. protecting
B. saving
C. polluting
D. fighting

[单项选择]We have made up our minds and nothing can prevent us ______ on the experiment.
A. from carried
B. from being carried
C. carrying
D. to carry

[单项选择]We wish the work could ______ more quickly, but we'd had some difficulties in getting the right kind of supplies.
A. have done
B. have been done
C. have been doing
D. be done

[单项选择]

Every day of our lives we are in danger of instant death from small high-speed missiles from space—the lumps of rocky or metallic debris which continuously bombard the Earth. The chances of anyone actually being hit, however, are very low, although there are recorded instances of "stones from the sky" hurting people, and numerous accounts of damage to buildings and other objects. At night this extraterrestrial material can be seen as "fireballs" or "shooting stars", burning their way through our atmosphere. Most, on reaching our atmosphere, become completely vaporised.
The height above ground at which these objects become sufficiently heated to be visible is estimated to be about 60-100 miles. Meteorites that have fallen on buildings have sometimes ended their long lonely space voyage incongruously under beds, inside flower pots or even, in the case of one that landed on a hotel in North Wales, within a chamber pot. Before the era of sp
A. big bright stars from space
B. man-made space vehicles
C. great interstellar dust clouds
D. small high-speed pieces of rock from space

[单项选择]—We have tried our best.
—You'd better give up, nowhere ______.


A. the missing girl could be found
B. you will find the missing girl.
C. could find the missing girl
D. could the missing girl be found

[单项选择]Next to natural resources comes the ability to ______ them to use.


A. take
B. set
C. get
D. turn

[单项选择]Our teacher says we've got to improve our pronunciation. What she says （　） to every one of us.
A. goes
B. applies
C. adapts
D. suits

[单项选择]— Are we supposed to take off our shoes before we enter
— No, you （　）.
A. shouldn't
B. needn't
C. mustn't
D. can't

[填空题]More natural resources （）(应该利用) to meet the increasing need of energy.