— Have you known each other for long?
— Not very long, we started to work in the pany.
A. after
B. before
C. when
Dsince
网友回答
A. after
B. before
C. when
(答案→)D. since
解析：since 是从属连词,引导时间状语从句,常与现在完成时连用。题中答语为省略句,补全为:We haven’t known each other very long. We have known each other since we started to work in the pany.