our teacher___be in his office because the lights off.A can't B.m_英语解答

our teacher___be in his office because the lights off.A can't B.mustn't
选哪个?为什么?

人气：371 ℃　时间：2020-01-27 09:32:52

解答

A.
can't表示否定的推测,意思是“不可能……”
mustn't意思是禁止,不允许