Question

1The windows must _________ before you leave the room.

A. be closed          B. are closed        C. close               D. be close

 

Answer 1

【答案】

A

【解析】含有情態(tài)動詞的被動語態(tài)。其結(jié)構(gòu)是“情態(tài)動詞+be+過去分詞”