题目

the teacher asked the students( ).a.whether they had ever seen the film avatar two months ago
b;that they had ever seen the film avatar two months before
c;if they had erer seen the film avatar two monrhs before
d;whether they have ever seen the film avarar two month before

提问时间：2020-08-01

答案

C
if they had ever seen the film Avatar two months before.
第一,这是个过去的过去的时态,因此用过去完成时.
第二,完成时不与表示时间的点的词ago连用,而改为表示时间段的词before