5. 由关系代词型what引导

That’s what I want to stress. 这是我想强调的。

That’s what we are here for. 我们来这里就为了这个。

Fame and personal gain is what they’re after. 他们追求的是名利。

He is no longer what he was. 他已经不是以前的他了。

6. 由as if / as though引导

It isn’t as if you were going away for ever. 又不是你离开不回来了。

Now it was as though she had known Millie for years. 现在好像她认识米莉已有好多年了似的。

It is not as though we were poor. 又不是我们家里穷。

7. 由because引导

It is because I love you too much. 那是因为我太爱你了。

That’s because you can’t appreciate music. 这是因为你不能欣赏音乐。

If I’m a bit sleepy, it’s because I was upall night. 如果我有点困，是因为一夜没睡。

It's because I passed a slip of paper for John to Helen in class. 这是因为我在上课中替约翰传纸条给海伦。

【注意】because 可引导表语从句，但与之同义的since, as, for等也不用于引导表语从句。

二、连词that的省略问题

引导表语从句的that通常不省略，但在口语或非正式文体中有时也可省略：

My idea is (that) we should do it right away. 我的意见是我们应该马上干。

The trouble is (that) he is ill. 糟糕的是他病了。