单项选择题

--What's the matter Why ______--The signal is against us.

A．the train stopping
B．does the train stop
C．is the train stopping
D．did the train stop
<上一题 目录 下一题>
热门 试题

单项选择题
They ______ us since five o'clock this morning until now.
A．are helping
B．help
C．have helped
D．have been helping
相关试题