不定式的句法
一、不定式用作主語(yǔ)
To see is to believe. 眼見(jiàn)為實(shí)。
To talk with him is a great pleasure. 和他談話是一件非常愉快的事。
To remember this is very important. 記住這一點(diǎn)很重要。
【注】為了避免頭重腳輕,在許多情況下,通常都將作主語(yǔ)的不定式置于句子后部,而在句首使用的主語(yǔ)位置使用形式主語(yǔ)it:
It’s very important to remember this. 記住這一點(diǎn)很重要。
It’s a pity to leave so early. 這么早走太遺憾。
二、不定式用作表語(yǔ)
He seems to be ill. 他似乎有病。
Her wish is to be a teacher. 她的愿望就是當(dāng)一名教師。
You are not to smoke in this room. 你不應(yīng)在這個(gè)房間里吸煙。
【注】不定式作表語(yǔ)主要有三種情況,一是用于seem, appear, prove, turn out等連系動(dòng)詞之后的不定式(尤其是to be),二是像My job is to sweep the floor(我的工作就是擦地板)這樣的主語(yǔ)與表語(yǔ)“等價(jià)”的情形,三是表示想法、約定、義務(wù)、命令、可能性、命運(yùn)等,再如:
We are to meet at the station at three. 我們約定3點(diǎn)鐘在車(chē)站見(jiàn)面。(表約定)
How are we to convince him? 我們?cè)趺茨苷f(shuō)服他呢? (表可能性)
You are to come when I call. 叫你來(lái)的時(shí)候,你必須來(lái)。(表命令)
三、不定式用作賓語(yǔ)
I can’t afford to buy a car. 我買(mǎi)不起汽車(chē)。
Remember to post the letter. 記住把信寄了。
I hope to be staying with you. 我希望和你住在一起。
【注】(1) 不定式不僅用作動(dòng)詞的賓語(yǔ),還可用作個(gè)別介詞(but, except)的賓語(yǔ):
I had no choice but to wait. 除了等,我沒(méi)有別的選擇。
It had no effect except to make him angry. 除惹他生氣外,沒(méi)產(chǎn)生任何效果。
(2) 當(dāng)作賓語(yǔ)的不定式后跟有賓語(yǔ)補(bǔ)足語(yǔ)時(shí),通常要用形式賓語(yǔ)it代替不定式,并將真正的賓語(yǔ)不定式置于賓語(yǔ)補(bǔ)足語(yǔ)之后:
I find it difficult to learn Japanese well. 我感到學(xué)會(huì)日語(yǔ)不容易。
四、不定式用作賓語(yǔ)補(bǔ)足語(yǔ)
Who taught you to drive? 誰(shuí)教你開(kāi)車(chē)的?
He warned me not to touch it. 他警告我不要碰它。
What caused him to change his mind? 什么使他改變主意的?
五、不定式用作定語(yǔ)
I have a question to ask you. 我有一個(gè)問(wèn)題要問(wèn)你。
It is a pleasant thing to remember. 這是一件值得記住的愉快的事。
He is not a man to tell a lie. 他不是個(gè)說(shuō)謊的人。
【注】有的名詞(如way, chance, right等)后用作定語(yǔ)的不定式可換成of doing sth:
It’s the best way to do [of doing] it. 這是做此事最好的辦法。
但是,以下名詞后接不定式作定語(yǔ)時(shí)通常不能換成of doing sth:
attempt 試圖 courage 勇氣
decision 決定 effort 努力
fortune 運(yùn)氣 failure 失敗
invitation 邀請(qǐng) permission 允許
promise 允諾 wish 愿望
六、不定式用作狀語(yǔ)
不定式作狀語(yǔ)可以表示多種關(guān)系(如目的、結(jié)果、原因、條件等):
I went to France to learn French. 我到法國(guó)去學(xué)法語(yǔ)。(表目的)
He returned home to find his wife waiting for him. 他回到家發(fā)現(xiàn)他的妻子在等他。(表結(jié)果)
You would make a great mistake to accept his offer. 你要是接受他的建議,你就犯了大錯(cuò)誤。(表?xiàng)l件)
We are proud to be members of this team. 作為這個(gè)隊(duì)的隊(duì)員我們感到很自豪。(表原因)
He opened his mouth as if to say something. 他張開(kāi)嘴,好像要說(shuō)什么。(表方式))