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【判断题】
多次弯曲造成的弯曲疲劳是钢丝绳破坏的主要原因之一。A.
正确
B.
错误
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举一反三
【单选题】—Hi, Tracy, you look tired. —I am tired. I ______ the living-room all day.
A.
painted
B.
have been painting
C.
had painted
D.
have painted
【单选题】—Hi, Winda, you look tired. —I am tired. I ______ the living-room all day.
A.
painted
B.
have been painting
C.
had painted
D.
have painted
【单选题】——Hi, Steve, you look tired. ——I am tired. I ______ the living room all the afternoon.
A.
painted
B.
had painted
C.
have been painting
D.
have painted
【单选题】Hi, Traly, you look tired. I’m tired. I the living room all day.
A.
painted
B.
had painted
C.
have been painting
D.
have painted
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