英语辅导：点击“疑问词+不定式”的用法

疑问词+不定式”是英语中很有用的结构。疑问词是疑问代词“who, whom, what, which, whose”和疑问副词“when, where, how”。 　　“疑问词+不定式”的结构主要有下列几种功用：
　　⑴作主语。如：
　　● When to hold the meeting has not yet been decided.
　　● How to cope with the rising cost of living becomes a daily discussion topic.
　　⑵作宾语。如：
　　● We must know what to say at a meeting.
　　● Do you know what to do?
　　⑶作表语。如：
　　● The problem is where to find the financial aid.
　　● The question is how to get there.
　　⑷作同位语。如：
　　● Tom had no idea which book to read first.
　　⑸用于双重宾语。如：
　　● I can tell you where to get this book.
　　● I asked him how to learn English.
　　注意：
　　1、并非所有动词都适用于“疑问词+不定式”结构，主要有：“know, see, decide, tell, ask, consider, discover, explain, forget, learn, remember, wonder, understand”等。
　　2、当这个结构作宾语时，它的作用相当于名词性从句。如：
　　● I could not decide which dictionary to buy. / I could not decide which dictionary I should buy.
　　● Jack did not know where to find such a good teacher./ Jack did not know where he could find such a good teacher.
　　3、有些动词，如“ask, show, tell, advise, inform, teach”等，可以先有个宾语，然后再接适当的“疑问词+不定式” 结构。如：
　　● The chief technician showed the apprentice how to repair the machine.
　　● Have you told him where to get the application form?