疑问词不定式结构

“疑问词+不定式动词”结构● xx英语有个很有用的结构，就是：疑问词+不定式动词（question word +to-infinitive）。

疑问词是疑问代词“who,whom,what,which,whose”和疑问副词“when,where, how, why ”。

此外，连接词“whether”也适用。

“疑问词+不定式动词”结构有何功用呢？其主要功用有下列五种：⑴当主语，如：● When to hold the meeting has not yetbeen decided.● Where to live is a problem.⑵当宾语，如：● We must know what to say at a meeting.● He could not tell whom to trust.● Do you know how to play bridge?⑶当补足语，如：● The p roblem is where to find the financial aid.● The question is who to elect.⑷当名词同位语，如：● Tom had no idea which book to read first.● Do you have a rough impression how to do it?⑸当宾语补足语，如：● Jim is not sure whose to choose.● Mary and John are not certain whether to get married or not.适用于“疑问词+不定式动词”的动词包括：“know, see, decide,tell,ask,consider,discover,explain,forget,guess,hear,imagine,inquire,learn, rember, think, wonder, understand”等。

有点值得特别注意的是：当这结构当宾语时，它的作用等于名词分句，例如：●Icouldnotdecidewhichdictonarytobuy./Icouldnotdecidewhichdictionary I should buy.●Jackdidnotknowwheretofindsuchagoodteacher./Jackdidnotknowwhere he could find such a good teacher.有些动词，如“ask, show, tell, advise, inform, teach”等，可以先有个宾语，然后才接着加上适当的“疑问词+不定式动词” 结构。

例如：●Thechieftechnicianshowedtheapprenticehowtorepairthemachine.● Have you told him where to get the application form?综上所述，可见“疑问词+不定式动词”结构是个形象清新，既容易用又不容易出错的特别结构，可以多多运用。

“疑问词+不定式”结构小结2010-04-06 21:25“疑问词+不定式”结构小结疑问词+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”。

一、几种用法：⑴作主语。

如：● When to hold the meeting has not yet been decided.⑵作宾语。

如：● We must know what to say at a meeting.⑶作表语。

如：● The problem is where to find the financial aid.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.二、注意事项：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,rember,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 decidewhich dictionary I should buy.●Jackdidnotknowwheretofindsuchagoodteacher./Jackdidnotknow 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：● Have you told him where to get the a pplication form?4、这种结构中，疑问代词须接及物动词或相当于及物动词的短语(who, which除外)【误】I don't know what to talk.【正】I don't know what to talk about.但可以说：We haven't decided who (which) to go.我们还没定谁(哪个)去。

5这种结构中的疑问副词后要接不及物动词；若接及物动词,要有动词的宾语。

I don't know how to talk.我不知如何谈。

I wonder if you could tell me how to do it.不知您能否告诉我如何去做这件事。

(不能说:... how to do.)三、考点例析：1. There isn't any difference between the two. I really don't know____.A. where to chooseB. which to chooseC. to choose whatD. to choose which考点："疑问词＋不定式"的语序；疑问词的选用。

2. I've worked with children before, so I know what ____ in mynew job.A. expectedB. to expectC. to be expectingD. expects考点：疑问词后接动词的用法。

家好，“疑问词+动词不定式”构成的不定式短语是本话题的语法“主角”。

想了解它的更多知识，请关注以下三个看点：第一看点：“疑问词+动词不定式”的个性此结构中疑问词包括疑问代词who,what,which以及疑问副词when,where,how等（不与why连用）。

这些“疑问词+动词不定式”结构经常放在forget, find out, discuss, decide, tell, teach, know,learn, wonder, rember等动词之后作宾语。

如：I don't know what to do.我不知道该做什么。

He told me how to answer all the questions in English.他告诉我怎样用英语回答所有的问题。

第二看点：“疑问词+动词不定式”的功用“疑问词+动词不定式”结构在句子中可以用作宾语、主语和表语等。

如：How to do it is a question.如何做是个问题。

（用作主语）He knows what to do and what not to do.他知道该做什么，不该做什么。

（用作动词宾语）The question is how to put it.问题是应该把它如何放才好。

（用作表语）第三看点：“疑问词+动词不定式”的转换“疑问词+动词不定式”结构相当于一个名词性从句，常常可用同等成分的从句代替。

改写后的句子需要在疑问词后加上相对应的主语，并要注意主谓语单复数的一致性。

如：The question is where to put it. →The question is where we should put it. 问题是应该把它放在哪里才好。

一些动词如tell, know, ask, show, teach, find (out), forget等都可接“疑问代（副）词（why除外）+不定式”作宾语，充当简单句，其意义相当于一个宾语从句。

这种句式可转化为含宾语从句的复合句。

当然在句型转换中，并非所有的宾语从句都能转换为“疑问词+不定式”结构。

看一下下面的情况：主句的谓语动词是decide, hope, wish, know, forget等时，句子中的“疑问词+动词不定式”结构可转化为宾语从句。

此时从句的主语和主句的主语相同。

如：We can'tdecide when to start. →We can't decide when we should start.We don't know what to do next. →We don't know what we should do next.注：主句的谓语动词是tell, ask, teach, show等，并且从句主语一致时，宾语从句可转化为“疑问词+不定式”结构。

如：Please tell us where we show our tickets.→Please tell us where to show our tickets。