首页 > 留学知识库

问题: 高一文科题(四)

We were just ( )the point of leaving the disco ( )a former schoolmate called us.
A.at,while
B.at,before
C.on,when
D.on,while
(选C为什么不对?)

解答:

be on the point of doing
表示正要……的时候
固定的句型
我选C 过去进行时的标志连词when