(1) what 引导主语从句
例：What surprised me is that everybody seemed to be very indifferent to her.
让我吃惊的是每个人似乎对她都很冷淡。
[ indifferent adj.不关心的;冷漠的]
(2) what 引导宾语从句
例：We can learn what we do not know.
我们能学会我们不懂的东西。
(3) what 引导表语从句
例：That is what I want.
那正是我所要的。
(4) what 引导同位语从句
例：I have no idea what they are talking about.
我不知道他们正在谈论什么。
