Robert is said abroad, but I don’t know in which country he is.A. have been studying B. to have been studying C. have studied D. to have studied

Robert is said abroad, but I don’t know in which country he is.
A. have been studying B. to have been studying C. have studied D. to have studied

答案B be said后应该接不定式形式,而且根据I don’t know in which country he is 意味着他现在仍然在国外学习,表示从过去到现在一直在做某事,要用完成进行体.所以选B,不能选D. 查看原帖>>
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