疑问代词有who（主格）,whom（宾格）,whose（所有格）,what 和 which 等.
疑问代词用于特殊疑问句中,一般都放在句首,并在句中作为某一句子成分.如：
Who is going to speak to us tomorrow?明天谁来跟我们讲话?（who作主语）
Who told you so?是谁告诉你的?（who作主语）
Whom are you talking about?你们在说谁?（whom 作宾语,但在句首时口语中常用who代替whom）
Whose umbrella is this?这是谁的伞?（whose作定语）
What is that?那是什么?（what 作表语）
What did he say?他说什么?（what 作宾语）
Which is yours,the blue pen or the red one?蓝笔和红笔哪一支是你的?（which 作主语）
注1：疑问代词who,what,which等后面加单词ever,可用来强调语气,表达说话人的各种感情.如：
What ever do you want?你到底想要什么?
Who ever is she looking for?她究竟是在找谁?
注2：which表示在一定数目（或范围）之内的选择,what则没有这种限制,如：
What do you usually have for lunch?你们午饭通常吃些什么?
Which do you prefer,rice or buns?米饭和馒头你爱吃哪个?
Which of you comrades come from the Northeast?你们同志们中间谁是东北人?
(希望有所帮助,