问题

the front door ___ ,he had to enter the room through the back door

A:Not knowing
B:Knowing not
C:Not known
D:Known not

正确答案是：

同类题型

The best selling MBA book ____ economics

Thank you _____ your help.

Practice more, _______ you’ll learn English better.

下列各句中，加点的成语使用恰当的一句是（）

In my senior high school, I will ______ than I did in my junior high school.