---When did you get to know each other ?
----It was in 2008 we spent summer vocation together.
A. that
B. when
C. before
D. since
网友回答
A. that
(答案→)B. when
C. before
D. since
解析：考查定语从句。先行词为2008，从句中缺少时间状语所以用关系副词when，句意：你们什么时候开始认识的？就是在我们一起度过暑假的2008年。所以选B。