题目内容
Experts ________ for Yetis in the Himalayas for years, but they still ________ one.
- A.have looked; haven’t been finding
- B.have looked; haven’t been found
- C.are looking; haven’t been found
- D.have been looking; haven’t found
句意为“专家们一直在喜马拉雅山寻找雪人好多年了,但一个也没有找到”。第一个空用have been doing表示“寻找”的状态一直持续了好几年,第二个空用现在完成时表示目前的状况。
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