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【单选题】
为防止泵油现象发生,一般第一道活塞环采用()环。A.
矩形环
B.
桶形环
C.
扭曲环
D.
三角环
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举一反三
【单选题】John and Mark became separated because ______.
A.
there wasn't room for both John and Mark on the buoy
B.
John couldn't control the coat and drifted away
C.
Mark thought it safe to stay on the buoy but John didn't
D.
John had to stay in the boat to radio for help
【简答题】A．Mr. Mark has much more time. B．Mr. Mark has a wife to help him. C．Mr. Mark doesn't have as much as responsibilities the interviewee has. D．Mr. Mark is not a book lover.
【简答题】1.When
he reads a book, his habit is to make a mark ___ the meaning is unclear to him.A. there B. wherever C. the place D. in which
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