疑问词who/what既可以作主语也可以作宾语,
作主语时,疑问词后面接的部分跟陈述句语序一样的,例如:
Who lives in this house?
What happened?
What's happening?
Who's got my key?
作宾语时,疑问词后面加助动词,例:
Who did you meet yesterday?
What did Paul say?
Who are you phoning?
What was Silvia wearing?
反过来推也一样,比如陈述句George likes oranges.
疑问句谁喜欢橘子,谁作主语,就是Who likes oranges?
疑问句George喜欢什么,什么作宾语,就是What does George like?