2、who 和whom只能独立使用,其中who可以作句子的主语、表语或动词的宾语,whom只能作谓语动词的宾语；而what、which、whose等既可以独立使用作主语、表语和宾语,也可以与名词构成疑问短语。如： Who is that man?(那男的是谁？) / What colour are their hats?(他们的帽子是什么颜色？) / Which car was made in Germany?(哪辆车是德国造的？)(被动句)
注意这个提问：The man in the car is my father.(车里的男人是我父亲)
→Which man is your father?(哪个男人是你的父亲？)
3、which除了可以询问指代的情况之外,还可以针对说明人物的时间、地点、岁数、颜色、大小、状况等进行提问。如：People there live a very sad life.(那里的人生活凄惨) →Which people live a sad life? (哪些人生活凄惨？)/ --Which hotel have you booked for your holiday?(为了度假你预订了哪家旅馆？)—The biggest one in Haikou.(海口最大的那家旅馆)
4、疑问代词不分单复数,视它所替代的人或事物决定单复数,但是通常用单数；如果修饰名词,则以名词的单复数为准。如：Who is (are) in that playhouse?(谁在游戏房里？) / What is that? (那是什么？)/ What are those? (那些是什么？) / What colours do they have?(它们有哪些颜色？)
