這種情況通常是將特殊疑問(wèn)詞引導(dǎo)的名詞性從句替換為特殊疑問(wèn)詞+不定時(shí).
具體情況和例句如下：
who what which when where how后加不定式在句中可以做主語(yǔ)、賓語(yǔ)、表語(yǔ)等,但why后加動(dòng)詞原型,是特例:
1.主語(yǔ)
e.g.when we will start has not been decided.可替換為When to start has not been decided.
何時(shí)動(dòng)身還未決定.
2.賓語(yǔ)
e.g.He did not know whether he should go there or not.替換為 He did not know whether to go there or not.
他不知該不該去那.
3.表語(yǔ)
e.g.The difficulty was how we could cross the river.替換為The difficulty was how to cross the river.
困難在于怎樣過(guò)河.
e.g.The question was where we should go.替換為The question was where to go.
問(wèn)題是去哪里?
4.雙重賓語(yǔ)
e.g.I can tell you where you can get this book.替換為I can tell you where to get this book.
我能告訴你從哪搞到這本書.
e.g.I asked him how I could learn English.替換為I asked him how to learn English.
我告訴他怎樣學(xué)好英語(yǔ).
5.有時(shí)疑問(wèn)詞前可用介詞
e.g.I have no idea of how Ican do it.替換為 I have no idea of how to do it.