问题
单项选择题
It is essential that these application()forms back as early as possible.
A.must be sent
B.will be sent
C.are sent
D.be sent
答案
参考答案:D
解析:
It is essential that…句型要求从句时态用should+动词原形;should常常被省略。这类关键词还有important,best,necessary,important,desirable,advisable,urgent,vital等。故选D。