表语从句最好区分了,系动词之后的是表语,所以系动词之后的是表语从句
系动词包括
一 be动词类：am、 is 、are 、was 、were
二 变化类：become、 get 、 turn 、 grow 、go
三 感官类:look 、sound、smell、taste、feel
四 延续类 ：remain 、stay 、keep
五 似乎类：appear、seem、look
举几个例子吧
The problem is who can drive the bus.
His suggestion is that we (should) have a meeting this afternoon.
Spring is when the flowers bloom.
其他动词之后的宾语为一个句子时,称之为宾语从句
We all know that he has studied English since 1998.
I will like whatever you give to me on my birthday.