The polar region is （）
A. a good place to land at by aeroplane
B. a good place to fly over
C. a good place to fly past
D. a good place to live in
Which of the following usually causes a tree to grow unhealthy（）
A. Giving a tree a special shape and a definite height.
B. Removing small side branches and making a tree look less thick.
C. Allowing too many branches to grow in the middle.
D. Having a tree surrounded by many other trees.
W: I don’t know why we listen to GeorgeM:（）
A. I don’ t know exactly why, either.
B. I guess we are wrong this time.
C. I know. But perhaps you don’ t know why.
D. George, you know, is one of the hardest working students among us.
57（）
A. say
B. describe
C. mention
D. write
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