how you什么词性

是副词词性，例如：

1、I don't know how you can say things like that.真想不到你怎么会说出这种话来。

2、I don't know how you stick that job.我不知道那活儿你怎么受得了。

3、I don't know how you can eat that stuff!我不明白你怎么能吃那种东西！

4、I don't see how you can equate the two things.我不明白你怎么能把这两件事等同起来。