2021考研英语基础语法大全：非谓语动词(8)
【动词非谓语形式–;–;不定式短语和疑问词连用】
(五)不定式短语和疑问词连用(who, whom, whose, what, which, when, where, how,还包括whether)
(1)做主语。
Who to turn to is what she wants to know. 找谁帮忙是她想知道的。
(2)做表语。
The question is which to take first. 问题是先拿哪一个。
(3)作宾语，常用这一结构作宾语的动词有ask, consider, decide discuss, explain, forget, find out, guess, inquire, know, learn, remember, see(=understand), show, settle(=decide), tell(=know), think, understand, wonder等。
I’ve found out where to buy them cheaply. 我发现了在哪里买这些东西便宜。
有些双宾语及物动词，也可用这个结构做直接宾语。常用的有tell, inform, show, advise, ask, teach,等。如：
I showed her how to use the remote control. 我向她演示怎样使用遥控器。
(4)做定语。
I must find a pen with which to fill in this form(=to fill in this form with). 我必须找支钢笔填表用。