非謂語是英語學習的重點也是難點，很多同學對這個語法知識一直是處於比較懵的狀態。其實只要掌握非謂語所充當成分的用法就可以運用自如了。

非謂語，顧名思義就是不做謂語的動詞的變化形式，即to do ，doing，done。除了謂語，句子成分中還有主語、賓語、表語、賓語補足語、定語和狀語。

下面看看不定式(to do)充當這6種成分的用法：

一、不定式作主語

1.To see is to believe. （這種情況不常用）

2. It is important to learn English well.

It 是形式主語，真正的主語是 to learn English well. 這種用法是常用的而且是考點！考點！考點！

二、不定式作表語: 常說明主語的內容、性質和特徵或表動作將要發生。

1. My job is to keep the children safe.

2.My task is to type the article.

三、不定式做賓語

1. He prefers to eat white bread and rice.
2. He wants to play football.

3.動詞feel, find, make, think等後面，可以用it作形式賓語代替真正的賓語——動詞不定式，句子結構是...feel / find / make / ... it+adj. / n.+to do...。

如：

I find it difficult to remember everything.

常接動詞不定式作賓語的動詞有：（需要記住！！！）

agree, afford, appear, ask, attempt；

care, choose, claim；

dare,decide,demand,deserve,determine；

expect, fail, get, guarantee；

hate, hesitate, hope, hurry；

intend, learn, manage, offer,

plan, prepare, pretend, promise；

refuse, seem, tend, threaten；

want, wish 等

四、不定式做賓語補足語

1. I'd invite her to have dinner at my house.

2 . We should allow the children to choose their own clothes.

Note 1: 帶to的動詞不定式作賓語補足語的動詞主要有：要求允許提議(ask, allow, advise)，期望邀請鼓勵(expect, invite, encourage)，教導告訴想要(teach, tell, want)，等待希望願意(wait for, wish, would like / love)。

Note 2:動詞不定式作補語，在主動語態句裡不帶to，被動語態句裡帶to時多數動詞是感官動詞和使役動詞，包括四“看”：look at, observe, see, watch，三“讓”：have, let, make，二“聽”：hear, listen to，一“感覺”：feel，一“注意”：notice。

如、1. I made him do his work.

2.He was made to do his work (by me).

變成被動，被省略的to 要還原。

Note 3: 不定式用在介詞but, except, besides後時,如果這些介詞前有行為動詞do的各種形式,那麼介詞後的不定式不帶to,相反則帶to.

如：1. She could do nothing but cry.

2. I have no choice but to go.

五、不定式做後置定語：只能用不定式做定語的情況很多，這裡只列出常用和常考的4點

1. 當修飾的名詞是抽象名詞（看得見摸得著的名詞是具體名詞，如鋼筆。看不見摸不著的詞是抽象名詞。），如：ability、 ambition、 attempt、 chance、 courage 、desire 、decision 、effort、 failure 、moment 、promise、 right 、time、 wish …（一些表示企圖、努力、願望、打算、能力等意義的名詞）

He made a promise to come here on time tomorrow.

2.當修飾的名詞前有the only, the next, the best, the first, the last, 以及由序數詞或形容 詞最高級修飾的名詞常常用不定式作定語。

He was the first one to think of the idea.

You are the only person to be late.

The manager is the last to come to the meeting.

3.當修飾的詞為 something, nothing, anything 等不定代詞時。

Do you have anything to say?

There is nothing to worry about.

4.當定語表示未來的還沒做的動作時。

The letter to be written is to my father.

The matter to be discussed is important.

六、用作狀語

1.目的狀語，置於句首或句末，置於句首時常表示強調。如：

1) To catch the early bus, she got up very early.

2)A group of young people got together to discuss this question.

3)She came to this city to visit her daughter.

2.原因狀語，多見於“sb.+be+adj.+to do...”結構句中。如：

I am very lucky to have him.

3.結果狀語，多見於“too...to”，“enough to...”結構句中。如：

1) I’m too tired to do it well.

2)The room is big enough for three people to live in.

不定式2種獨立用法

一、獨立結構：

to be frank,

to be honest,

to tell the truth

這三個詞組是同義詞，意思是“說實話”、“老實說”或“坦率地說”

To tell the truth, I am not happy at the moment.

二、與疑問詞連用：不定式與疑問詞who,which, when, how, what 等連用，在句中起名詞作用，可充當主語、表語、賓語等。

He didn’t know what to say.(賓語)

How to solve the problem is very important.(主語)

My question is when to start. (表語)

練一練吧

單選：

1. This company was the first ____ portable radios as well as cassette tape recorders in the world.

A. producing B. to produce C. having produced D. produced

2. The purpose of new technology is to make life easier, ____it more difficult.

A .not making B. not make C .not to make D. nor to make

3. Helen had to shout ______above the sound of the music .

A .making herself hear B. to make herself hear

C. making herself heard D .to make herself heard

4. I don’t know whether you happen_______ ,but I am going to study in the U.S.A this September.

A .to be heard. B. to be bearing C .to hear D .to have heard

5. The news reporters hurried to the airport, only ______the film stars had left.

A .to tell B .to be told C .telling D .told

6. You were silly not _______your car.

A. to lock B. to have locked C. locking D. having locked

7. The teacher asked us ______so much noise.

A .don’t make B. not make C. not making D .not to make

8. An army spokesman stressed that all the soldiers had been ordered _____clear warnings before firing any shots.

A .to issue B. being issued C. to have issued D. to be issued

9. I’d rather have a room of my own, however small it is, than_______ a room with someone else.

A. to share B. to have shared C. share D. sharing

10. The bank is reported in the local newspaper_________ in broad daylight yesterday.

A. robbed B. to have been robbed C. being robbed D. having been robbed