Itwasn’tuntil

问题详情：

 It wasn’t until_______that_______to prepare their lessons.

A. did the teacher come in; the students began

B. the teacher came in; the students began

C. did the teacher come in; did the students begin

D. the teacher came in; did the students begin

【回答】

【解析】选B。考查含有not . . . until的强调结构。句意: 直到老师进来，学生们才开始准备功课。“It was not until . . . that . . . ”，主句和从句都用陈述语气。

知识点：一般过去时及其被动式

题型：选择题