疑问代词包括：who/whom, which, what, whose，用于引导特殊疑问句。Who/whom指人，who在句中做主语,whom做宾语，在口语中who可以代替whom。What，which，whose可以单独使用，也可以修饰名词。修饰名词时，三者意义有所不同，例如：whose books(谁的书)，which books(哪几本书)，what books(什么书)。

　　【例句】

　　Who is that fellow standing there, doing nothing?

　　Whose money is it, his or hers?

　　What do you want to drink, black coffee or coffee with milk?

　　Which is the best idea among all these choices?