1主语
It is a fact that he is a good boy!
It is important/necessary ...that...
It is known to us how he became a writer
The problem is what he has done to de boy~
what he wants to tell us is not clear!
2宾语
I want to konw what he has told you.
I don't care about whether you have money or not.
时态问题要注意.We knew that he had earned enough money to buy it.主语过去,宾语过去完成.但是下面例外：客观真理,科学,自然现象.
the teacher told us that the sun rises（真理一般时态） in the east
否定转移.I don't think he will do so.宾语一般不用否定语气
3表语
it looks as if it is going to rain
the fact is that he lost the game
the reason why he was late was that （不可以用because）.
4同位语
I have no idea when he wil be back