疑问词+动词不定式 I can't decide ______________________A what to eatB.how to eatC.where to eatD.when to eat

疑问词+动词不定式 I can't decide ______________________A what to eatB.how to eatC.where to eatD.when to eat 什么叫动词跟疑问词加不定式? 那些动词后可以+疑问词+不定式 疑问词+助动词+主语+动词 = 疑问词+不定式?区别?用法? I can't choose which book to buy.为什么用to buy?是动词不定式作定语修饰book吗? Simon doesn't know what to do.将句子转换成wh-疑问词+动词不定式的简单句 疑问词加动词不定式到底可以干什么啊 英语 疑问词加不定式There are so many kinds of tape-recorders on sale that I can't make up my mind which to buywhich to buy做从句的什么成分,定语还是宾语补足?为什么? I haven't decided which train I should take.(用动词不定式改写句子)顺便解释一下什么是动词不定式 动词后能跟不定式的都可以疑问词+不定式吗? 1.there isn't much I can do to help him这句话里怎么有4个动词（系动词 情态动词 实义动词 不定式）为什么不是I can help him,加do干嘛?2.he hasn't got as much work to do as I have.这句话里为什么有to do? 特殊疑问词动词不定式有动词不定式都是特殊疑问词+to do ,那么如 how far ,whose sth.后也可同样+to do sth么? I can help you to solve this problem.为什么要加动词不定式? I can speak a little english 哪个是情态动词.哪个是不定式.指出来 疑问词加不定式I dont't know how to do it.一定要加it吗?为什么?这句话是宾语从句吗? 疑问词加不定式做介词宾语时的介词是什么例如：I don`t know how to improve my English.中的介词是什么呢? I'm new here.-Don't worry.I'll do what I can to help you.中what .you是宾语从句吗?或是在这里to help是动词不定式,是宾补,请问怎么样才算是宾补呢? I don't have enough time to spend with her.中的动词不定式做什么成分