So far, the moon ________ by man already.

A. is visited
B. will be visited
C. has been visited
D. was visited

答案C
so far及already都是现在完成时的时间状语,而主语为the moon,故此句应为现在完成时的被动语态,所以选C。
温馨提示:答案为网友推荐,仅供参考
相似回答