Question

Helen ______ her keys in the office so she had to wait until her husband ______ home.

[　　]

A．has left, come

B．left, had come

C．had left, came

D．had left, would come

Answer 1

答案：C
提示：

因为把钥匙落在家里和后面的有时间先后关系所前要用完成，而他回来，则是某一时间点发生的动作，只用一般过去时就可。