Question

Hi, Bob. How are you doing? It has been a long time _____ we left our junior middle school

1. A.
   when
2. B.
   that
3. C.
   before
4. D.
   since

Answer 1

D
试题分析：此处主句是现在完成时，从句是一般过去时，所以选since。句意：Bob你过得怎么样？自从我们初中毕业很长时间了。
考点：考查状语从句的连接词。