考博網(wǎng)上培訓

考博英語語法詳解
　　(2)介詞except和but作“只有…，只能…”講時跟不定式結(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)在表示生理感覺的動詞后的不定式不帶to。這類詞有：
　　feel　覺得　observe 注意到，看到　overhear聽到
　　watch注視　listen to聽　perceive察覺，感知
　　notice注意　see看見　look at看　hear聽
　　On seeing the young child fell into the lake，Eric sprang to his feet，and went on the rescue.
　　2)另一類是某些使役動詞，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。
　　(注)：
　　①上述感覺動詞與使役動詞轉(zhuǎn)換為被動結(jié)構(gòu)時.其后的不定式一般需帶to，如：
　　He was seen to come.
　　The boy was made to go to bed early.
　　②在動詞find與help之后，不定式可帶to亦可不帶to，如:
　　He was surprised to find the sheep (to) break fence at this season.他發(fā)現(xiàn)羊在此季節(jié)越出柵欄，感到驚訝。