代词
3、无论是做疑问代词还是限定词，which 和 what 所指的范围不同。what所指的范围是无限的，而which则指在一定的范围内，例如：
Which girls do you like best?
你喜欢哪几个姑娘?
What girls do you like best?
你喜欢什么样的姑娘?
4、who通常作主语和表语，whom作宾语，例如：
Who is to take the chair? 谁做主席?
Who is speaking? 是哪一位(打电话)?
Who(m) did you meet on the street?
你在街上遇到了谁?(作动词宾语)
Who(m) are you taking the book to?
你要把这书带给谁?(作介词宾语，置句首)
To whom did you speak on the campus?
你在校园里和谁讲话了?(作介词宾语，置介词 后，不能用who取代。)
5、Whose, what, which这三个疑问代词可以用作：
(1) 主语：
What happened next? 后来怎么样了呢?
Whose is better? 谁的好一些?
Which is yours? 哪是你的?
