一、后接名词时的区别
当用作定语修饰其后接名词时,只用which和what,不能用who。which和what的区别是:前者用于选择范围较小或较明确的场合,后者用于选择范围较大或不明确的场合。如:
Which color do you like, black or white? 黑色和白色,你喜欢哪种?
Which is bigger, the sun or the earth? 太阳和地球哪个大?
What color is your car? 你的汽车是什么颜色的?
但是,若指人,即使选择的范围不明确,也可用which。如:
Which [What] writers do you like? 你喜欢哪些作家?
二、其后不接名词时的区别
当其后不接名词时,三者均可用,which和what的用法区别依然是:前者用于选择范围较小或较明确的场合,后者用于选择范围较大或不明确的场合。如:
Which is in the box, the red one or the black one? 哪一个在盒子里,是红色的那个还是黑色的那一个?
What is in the box? 盒子里装的是什么东西?
至于who,它一般只用来指人,不管选择范围大还是小、明确还是不明确均可用。如:
Who won –– Tom or Mike? 谁赢了,是汤姆还是迈克?
Who is your favorite poet? 你最喜欢的诗人是谁?
注:当选择范围比较明确且用作宾语时,who也可以用which或which one代之。如:
Who [Which / Which one] do you like better, your father or your mother? 你更喜欢谁,父亲还是母亲?
三、与else以及of短语搭配时的区别
1. 正由于what和who的选择范围可以很大或不明确,所以其后可以跟 else,但一般不跟表示特定范围的of短语。如:
What else have you bought? 你还买了些什么?
Who else was at the party? 聚会上还有谁?
在你的老师之中,你最喜欢哪一位?
正:Which of your teachers do you like best?
误:Who [What] of your teachers do you like best?
我们当中谁去洗衣服?
正:Which of us is going to do the washing?
误:Who of us is going to do the washing?
这些词典当中哪一本是你的?
正:Which of these dictionaries is yours?
误:What of these dictionaries is yours?
2. 而which 的选择范围相对比较小或明确,所以其后一般不接else,但却常与表特定范围的of短语连用:
Which of the three girls is the oldest? 这三个女孩中哪个年纪最大?
Which of the boys is the strongest? 这些男孩当中,哪一个力气最大?
你还要点别的什么吗?
正:What else would you like?
误:Which else would you like?
四、口语中的用法区别
比较以下三组对话,注意体会它们的区别:
A:Who is he? 他是谁?
B:He is Mary’s husband. 他是玛丽的丈夫。
注:Who is he? 的意思是要了解他的一些情况。
A:What is he? 他是干什么的?
B:He is an English teacher. 他是英语教师。
注:What is he? 的意思是询问他的职业。
A:Which is he? 哪位是他?
B:The one by the window. 窗户边的那位。
注:Which is he? 的意思是要在几个人中辨别要找的人。