“please be very quiet”这句话中,为什么要用“be”呢?

题目

“please be very quiet”这句话中,为什么要用“be”呢?

答案

祈使句中,please 后要接动词原形.
be very quiet中, be 是这个词组的动词. 所以用 be
如果在陈述句中,要根据主语变的.如
He is very quiet.
I am very quiet.
They are very quiet.