非謂語(yǔ)動(dòng)詞常考的其它結(jié)構(gòu)
(1)疑問(wèn)詞+不定式結(jié)構(gòu)
疑問(wèn)詞who，what，which，when，where和how后加不定式可構(gòu)成一種特殊的不定式短語(yǔ)。它在句中可以用作主語(yǔ)、的賓語(yǔ)、的表語(yǔ)和雙重賓語(yǔ)。如：
When to start has not been decided.何時(shí)動(dòng)身尚未決定。(主語(yǔ))
I don’t know what to do.我不知道該怎么辦。(賓語(yǔ))
The difficulty was how to cross the river.困難在于如何過(guò)河。(表語(yǔ))
I can tell you where to get this book.我可以告訴你哪里可以買(mǎi)到此書(shū)。(雙重賓語(yǔ))
(注)A.有時(shí)疑問(wèn)詞前可用介詞，如：
I have no idea of how to do it.我不知道如何做此事。
B.動(dòng)詞know 后面不能直接跟不定式作賓語(yǔ)，只能跟疑問(wèn)詞(如：how, what)+不定式：
While still a young boy, Tom knew to play the piano well and as he grew older, he wrote operas, the most famous of which is Carmen.
(2)介詞except和but作“只有…，只能…”講時(shí)跟不定式結(jié)構(gòu)(but與不帶to的不定式連用)。
When the streets are full of melting snow, you cannot help but getting your shoes wet.
(3)不帶to的不定式
1)在表示生理感覺(jué)的動(dòng)詞后的不定式不帶to。這類(lèi)詞有：
feel 覺(jué)得 observe 注意到醫(yī)學(xué)全在,線gydjdsj.org.cn，看到 overhear聽(tīng)到
watch注視 listen to聽(tīng) perceive察覺(jué)，感知
notice注意 see看見(jiàn) look at看 hear聽(tīng)
On seeing the young child fell into the lake，Eric sprang to his feet，and went on the rescue.
2)另一類(lèi)是某些使役動(dòng)詞，如make, let，have等。如：
Let him do it.讓他做吧。
I would have you know that I am ill.我想要你知道我病了。
