Question

Helen ________ her key in the office so she had to wait until her husband ________ home.

A. had left; came

B. has left; comes

C. left; had come

D. had left; would come

 

Answer 1

答案：A
解析：

Leave这个动作发生在had to wait之前，因此要用过去完成时；until引导的是时间状语从句，用一般过去时即可。