How time flies! It’s almost three years we met last time.A. whenB. beforeC. whileD. since

问题补充：

How time flies! It’s almost three years we met last time.

A. when

B. before

C. while

D. since

答案：

A. when

B. before

C. while

(答案→)D. since

解析：此题重点考查句型结构it’s+段时间since+句子表示从…以来已经多久；