It was essential that the application forms ___ back before the deadline.

2023-05-26

A.would be sent
B.were sent
C.be sent
D.must be sent

参考答案:C

本题考查虚拟语气的用法:在句型It‘s +adj.+that从句中,如果adj.是essential,necessary,natural等的话,that从句中用sb. should do,should可以省略。题目意为“申请书要在截至日期前送回来这是最基本的。”因此选C。