[高中]全新語法:動(dòng)詞不定式 四、不定式特殊句式

四、不定式特殊句式

1.疑問詞+to do sth.

（1）做主語

Where to go tomorrow has not been decided.明天到什么地方去尚未決定。

It is still a question how to divide labor among the workers.

這些工人之間如何分工仍是個(gè)問題。

When to start still remains a question.何時(shí)出發(fā)還是個(gè)問題。

it still remains a question when to start.何時(shí)出發(fā)還是個(gè)問題。

（2）作動(dòng)詞賓語

I know where to find the boy.我知道到哪里能找到這個(gè)男孩。（作動(dòng)詞know的賓語）

I asked her how to learn English.我問她如何學(xué)英語。（作直接賓語）

Will you please show me how to get to the nearest bank？

你能告訴我去最近的銀行怎么走嗎？（作直接賓語）

【提示】 動(dòng)詞show，know 只能用“疑問詞+to do”不定式短語作賓語。

（3）作介詞賓語

He has no idea of how to answer this question.他不知道怎樣回答這個(gè)問題。

He thought a lot about how to improve the crop.他對(duì)如何提高收成考慮得很多。

We must first solve the problem of whom to serve.我們必須首先解決為誰服務(wù)的問題。

【提示】 有時(shí)定語從句也可以簡(jiǎn)化為“介詞+which （關(guān)系代詞）+to do sth.” 形式。

Della had only $1.87 with which to buy Jim a present.德拉僅有$1.87來為吉姆買一件禮物。

You have a number of topics from which to choose.你有很多題目可以選擇。

（4）作表語

The question is which to choose.問題是挑選哪一個(gè)。

The most difficult challenge is how to survive without friends.

最難的挑戰(zhàn)，就是生活中孤獨(dú)無友。

2.for sb.to do sth.

（1）作主語

It is important for you to find a job.對(duì)你來說找份工作是重要的。

It isn’t right for people to laugh at others.人們嘲笑別人是不對(duì)的。

【提示】 for后的sb.是動(dòng)詞不定式的邏輯主語，即to do這一動(dòng)作的執(zhí)行者。

（2）作賓語

I consider it necessary for her to learn French.我認(rèn)為她需要學(xué)法語。

We must try to make it possible for lost time to be recovered.

我們必須努力奪回失去的時(shí)間。

【提示】 “for sb.to do ...”作賓語時(shí)，常用it作形式賓語。

（3）作表語

It’s for you to decide what to do next.得由你來決定下一步該做什么。

What I want is for you to have a rest.我希望的是你先休息一下。

（4）作定語

It’s time for us to go to bed.現(xiàn)在是我們睡覺的時(shí)候了。

There’s no reason for you to be late.你沒有理由遲到。

（5）作狀語

He stood aside for her to pass.他站在一邊讓她過去。（作目的狀語）

The lesson is too easy for them to read.這一課對(duì)他們來說太容易了。（作結(jié)果狀語）

3.It is+形容詞+for sb.to do sth.

certain 肯定　　　　　clear 清晰的　 　　dangerous 危險(xiǎn)的　　　　　difficult 困難的

easy 容易的　　　　　 fit 恰當(dāng)?shù)摹　　?　hard 艱難的　　　　　　　 important 重要的

impossible 不可能的　 illegal 非法的　　　legal 合法的　　　　　　　likely 可能的

necessary 必要的　　　obvious 明顯地　　　possible 可能的　　　　　 proper 合適的

suitable 適當(dāng)?shù)摹　　?useful 有用的

It’s impossible for me to be with you.同你在一起我覺得不可能。

It’s very dangerous for children to cross the busy street.

對(duì)孩子們來說，穿過繁忙的街道很危險(xiǎn)。

It’s difficult for us to finish the work.對(duì)我們來說，完成這項(xiàng)工作很困難。

It is necessary for us to master a foreign language.對(duì)我們來說精通一門外語是必要的。

4.It is+形容詞+of sb.to do sth.

brave 勇敢的　　　　　careful 細(xì)心的　　　　　careless 粗心的　　　　　clever 聰明的

considerate 體貼的　　crazy 瘋狂的　　　　　　cruel 殘忍的　　　　　　 foolish 傻的

good 好的　　　　　　 honest 誠實(shí)的　　　　　 impolite 沒禮貌的　　　　kind 善良的

lazy 懶惰的　　　　　 naughty 淘氣的　　　　　nice和藹的　　　　　　　 polite 有禮貌的

right 正確的　　　　　rude 粗魯?shù)摹　　　　　?selfish 自私的　　　　　 silly 愚蠢的

stupid 笨的　　　　　 unkind 不友好的　　　　 unselfish 無私的　　　　 unwise 不明智的

wise 聰明的　　　　　 wrong 錯(cuò)誤的

It is very kind of you to help me out.幫我們擺脫困境太感謝你了。

It seemed selfish of him not to share his dictionary with others.

他很自私不和其他人共用他的詞典。

It’s silly of you to do such a thing.做這樣的事你真傻。

It’s wrong of the other children to make fun of you.別的孩子取笑你是不對(duì)的。

【提示】

“It is+形容詞+of sb.to do sth.” 句式中，of的賓語可變?yōu)橹髡Z，不定式作狀語的句式。

It is careless of him to lose so many things.他丟了這么多東西，真是太粗心了。

He is careless to lose so many things.

【辨析】有個(gè)好身體對(duì)我們來說是很重要的。

【正】It is important for us to have good health.

【誤】It is important of us to have good health.

【誤】We are important to have good health.

5.be to do sth.

（1）打算、決定、計(jì)劃、安排等。

He is to visit Japan next week.他決定下周訪問日本。

I was to have told you yesterday，but you were not in.

我本打算昨天告訴你的，但你不在家。

【提示】 be to have done表示本打算干，事實(shí)上沒有干成。

I was to have seen him last Wednesday but he did not come.

我本來上周三就能見到他的，可他沒來。

（2）指示、命令、禁止等，意為“必須，一定”。

You are to hand in the exercises tomorrow.你們明天必須交練習(xí)。

You’re not to smoke here.你不可以在此處抽煙。

（3）責(zé)任、義務(wù)、需要，意為“該不該”。

Who is to blame？ 誰該負(fù)責(zé)？

You are to report to the police.你應(yīng)該報(bào)警的。

（4）可能性，與can，may 相當(dāng)，不定式多用被動(dòng)式。

The book was not to be found.那本書可能找不到了。

the book could not be found.

（5）假設(shè)，用于虛擬條件句中。

If it were to rain，we would get wet.要是下雨，我們就會(huì)淋濕。

If I were to meet her tomorrow，I would ask her about it.

若是明天能見到她，我就會(huì)問她這件事。

（6）be about to do 剛打算，即將做

I was about to speak when Mary spoke first.我正要講話，瑪麗先開口說了。

I was on the point of speaking when Mary spoke first.

【提示】 be about to不與具體的時(shí)間狀語連用。

6.be said to do sth.

They are said to leave soon.據(jù)說他們很快就要離開。（將來）

His company is said to be in trouble.據(jù)說他的公司遇到了困難。（現(xiàn)在）

He is said to be doing fine at school.據(jù)說他在學(xué)校表現(xiàn)很好。（現(xiàn)在）

They are said to have left London.據(jù)說他們已經(jīng)離開倫敦。（過去）

There is said to be plenty of oil off our coast.據(jù)說我國沿海有大量的石油。（現(xiàn)在）

There is said to have been an earthquake in Japan.據(jù)說日本發(fā)生了一次地震。（過去）