It is almost five years we saw each other last time.A. beforeB. sinceC. afterD. when

问题补充：

It is almost five years we saw each other last time.

A. before

B. since

C. after

D. when

答案：

A. before

(答案→)B. since

C. after

D. when

解析：解此题的关键在于主句与从句在时态上保持一致。用A、C、D三项的连接词引导时间状语从句时，与主句的时态明显不一致。since引导从句时常用过去时，主句则用一般现在时或现在完成时。