what常用来引导名词性从句,一种提出具体问题,另一种相当于汉语的“所...的”,称作关系代词型连接代词.分述如下：
一、提出具体问题,用于宾语从句.
1. Please let me know what you are going to do.
请告诉我你打算做什么.
2. I wonder what you will give me for my birthday present.
我很想知道你将给我送什么样的生日礼物.
二、关系代词型名词从句
1. 宾语从句：He will take what you offer him.
他将接受你所送给他一切东西.
2. 主语从句：What happened after that was interesting.
在那以后所发生的事情很有趣.
3. 表语从句：That was what I had told you all about it.
那就是我所告诉过你的一切事情.
