[单项选择]We found （shelter） from the rain under the tree.
A. defense
B. standing
C. protection
D. room

[单项选择]We found （shelter） from the rain under the trees.
A. defense
B. standing
C. protection
D. room

[单项选择]We have been told that under no circumstances we can use the telephone in the office for personal affairs.（）
A. did we use
B. may we use
C. we may use
D. we could use

[单项选择]（　） the rain we should have had a pleasant journey.
A. As for
B. But for
C. For
D. With

[单项选择]（　） the rain we would have had a nice holiday.
A. But that
B. But for
C. Despite
D. In spite of

[单项选择]______ the heavy rain we stayed at home the whole morning.


A. Owing to
B. But for
C. Instead of
D. Due of

[单项选择]The road was under repair so we had to go round．


A. 正在修路，我们只好绕道而行。
B. 路还没修好，我们只好下车四处走走。
C. 马上要修路，所以我们的行程被耽搁了。
D. 马上要修路，所以我们只好绕路。

[单项选择]From that we read we can infer that "it was a normal day in the life of the American Red Cross in Greater New York" means its staff ______.
A. deal with the fall of houses in the city every day
B. are busy helping people who suffer from disasters every day
C. work during the day and to have banquet in the evening every day
D. go to Harlem, the poorest district of New York, every day and help people there

[单项选择]

What makes it rain Rain falls from clouds for the same reason anything falls to Earth. The Earth’s gravity pulls it. But every cloud is made of water droplets or ice crystals. Why doesn’t rain or snow fall constantly from all clouds The droplets or ice crystals in clouds are exceedingly small. The effect of gravity on them is minute. Air currents move and lift droplets so that the net downward displacement is zero, even though the droplets are in constant motion.
Droplets and ice crystals behave somewhat like dust in the air made visible in a shaft of sunlight. To the casual observer, dust seems to act in a totally random fashion, moving about chaotically without fixed direction. But in fact dust particles are much larger than water droplets and they finally fall. The average size of a cloud droplet is only 0. 0004 inch in diameter. It is so small that it would take sixteen hours to fall half a mile in perfectly still air, and it does not fall out of mo
A. They never occur.
B. They are not affected by the force of gravity.
C. In still air they would fall to earth.
D. In moving air they fall at a speed of thirty-two miles per hour.