眾所周知，不定式動(dòng)詞（Infinitive）的形式是：“to + 原動(dòng)詞”, 如：to come, to go, to play, to read, to listen, to sing等等。
在一般情況下，“to + 原動(dòng)詞”必須靠攏，但在某些情況里，“to”和原動(dòng)詞可以被適當(dāng)?shù)母痹~（Adverb）分開，在某些動(dòng)詞句型里，“to”則必須省略。
在什么情況下，不定式動(dòng)詞的兩部份可以分開呢？分開的目的何在？在大多數(shù)場(chǎng)合里，不定式動(dòng)詞兩部分不分開，只有在特殊環(huán)境里才準(zhǔn)許讓副詞加入，以便更準(zhǔn)確地，更自然地反映某些實(shí)際情況?？纯聪旅嫒齻€(gè)句子：
（1） Bob failed completely to fulfil his duties.
（2） Bob failed to fulfil his duties completely.
（3） Bob failed to completely fulfil his duties.
在（1）里，狀態(tài)副詞“Completely”既可修飾謂語動(dòng)詞“failed”，也可修飾不定式動(dòng)詞“to fulfil”。在 （2） 里，“completely”和被修飾的不定式動(dòng)詞離開太遠(yuǎn)，力道不足，效果欠佳。在 （3） 里，“completely”夾在不定式動(dòng)詞兩部份之間，把它修飾得既自然又貼切；這個(gè)位置，在三個(gè)句子中，可說是最恰當(dāng)?shù)牧恕?BR> 同樣的，（4）比（5）緊湊；（6）比（7）扎實(shí)：
（4） It was wrong for Mr Lim to suddenly quit the job.
（5） It was wrong for Mr Lim suddenly to quit the job.
（6） Is it possible for a chaotic country to further develop its economy?
（7） Is it possible for a chaotic country to develop its economy further?
由于不定式動(dòng)詞的兩部分在適當(dāng)時(shí)分開有其優(yōu)點(diǎn)，這種用法，在現(xiàn)代英語里越來越普遍。例如：
（8） Civil servants were urged to better serve the public.
（9）The Economic Development Board has just announced some new plans to further promote the economic development.
（10） I don't want you to be forever criticising your friends' good efforts.
（11） The new manager wanted the new scheme to be properly implemented.
最后，順便談?wù)勈裁辞闆r下，不定式動(dòng)詞中的“to”要省略。
一、和“make, let”, 及感官動(dòng)詞“see, hear, watch”連用的句型中，“to”必須省略。例如：
（12） Don't make her cry.
（13） I won't let you go now.
（14） We saw a man jump into the lake.
（15） Have you heard me call you ?
（16） Let us go to watch him play the game.
二、在“had better, would rather”后面的不定式動(dòng)詞中的 “to”要省略。例如：
（17） You had better do the work now.
（18） It is late now. I would rather go tomorrow.
要注意的是，在被動(dòng)語態(tài)中“to”這符號(hào)可能要重現(xiàn)。例如：
（19） Noone can make him understand the real problem. → He cannot be made to understand the real problem.
（20） We heard them speak English.→They were heard to speak English.
在一般情況下，“to + 原動(dòng)詞”必須靠攏，但在某些情況里，“to”和原動(dòng)詞可以被適當(dāng)?shù)母痹~（Adverb）分開，在某些動(dòng)詞句型里，“to”則必須省略。
在什么情況下，不定式動(dòng)詞的兩部份可以分開呢？分開的目的何在？在大多數(shù)場(chǎng)合里，不定式動(dòng)詞兩部分不分開，只有在特殊環(huán)境里才準(zhǔn)許讓副詞加入，以便更準(zhǔn)確地，更自然地反映某些實(shí)際情況?？纯聪旅嫒齻€(gè)句子：
（1） Bob failed completely to fulfil his duties.
（2） Bob failed to fulfil his duties completely.
（3） Bob failed to completely fulfil his duties.
在（1）里，狀態(tài)副詞“Completely”既可修飾謂語動(dòng)詞“failed”，也可修飾不定式動(dòng)詞“to fulfil”。在 （2） 里，“completely”和被修飾的不定式動(dòng)詞離開太遠(yuǎn)，力道不足，效果欠佳。在 （3） 里，“completely”夾在不定式動(dòng)詞兩部份之間，把它修飾得既自然又貼切；這個(gè)位置，在三個(gè)句子中，可說是最恰當(dāng)?shù)牧恕?BR> 同樣的，（4）比（5）緊湊；（6）比（7）扎實(shí)：
（4） It was wrong for Mr Lim to suddenly quit the job.
（5） It was wrong for Mr Lim suddenly to quit the job.
（6） Is it possible for a chaotic country to further develop its economy?
（7） Is it possible for a chaotic country to develop its economy further?
由于不定式動(dòng)詞的兩部分在適當(dāng)時(shí)分開有其優(yōu)點(diǎn)，這種用法，在現(xiàn)代英語里越來越普遍。例如：
（8） Civil servants were urged to better serve the public.
（9）The Economic Development Board has just announced some new plans to further promote the economic development.
（10） I don't want you to be forever criticising your friends' good efforts.
（11） The new manager wanted the new scheme to be properly implemented.
最后，順便談?wù)勈裁辞闆r下，不定式動(dòng)詞中的“to”要省略。
一、和“make, let”, 及感官動(dòng)詞“see, hear, watch”連用的句型中，“to”必須省略。例如：
（12） Don't make her cry.
（13） I won't let you go now.
（14） We saw a man jump into the lake.
（15） Have you heard me call you ?
（16） Let us go to watch him play the game.
二、在“had better, would rather”后面的不定式動(dòng)詞中的 “to”要省略。例如：
（17） You had better do the work now.
（18） It is late now. I would rather go tomorrow.
要注意的是，在被動(dòng)語態(tài)中“to”這符號(hào)可能要重現(xiàn)。例如：
（19） Noone can make him understand the real problem. → He cannot be made to understand the real problem.
（20） We heard them speak English.→They were heard to speak English.