疑问代词包括what， which， who， whom， whose， 可以用来构成特殊疑问句，也可以引导名词从句。 What， which， who在句子中作主语或宾语，whom作宾语，whose作定语。如：

　　Who is speaking? (主语)

　　Which do you prefer， the yellow one or the white one? (宾语)

　　Whats your sister?(表语)

　　The man who is talking with my mother is an engineer。(引导定从句)

　　The old man whose son is studying abroad is our formal dean of the department. (引导定从句)

　　This is the plane which will fly to Wuhan this afternoon. (引导定从句)

　　I dont remember whom I have lent my dictionary to. (引导宾语从句)

　　疑问代词what， which， who， whom后面可以加ever来加重语气。如：

　　Whoever can be calling at this time of the night ?谁这么深更半夜来找人？

　　Ill say whatever comes into my head。

　　Take whichever book you like。