什么是主语状从

句子的主语部分不是一个词而是一个句子。如
What you said made me angry.
What you said是主语 made是谓语 me 宾语 angry 宾补

1.It is important that we all should attend the meeting.

2. It is strange that the man should have stuck to his silly ideas.

3.That he finished writing the composition in such a short time surprised us all.

4.Whether we will go for an outing tomorrow remains unknown.

5.Who will be our monitor has't been decided yet.

6. Whom we must study for is a question of great importance.