高考英语语法：不定式

不定式

一、动词不定式的性质

1. 不定式的动词性质表现在：可有时态和语态的变化,可有自己的宾语和状语并与其组成不定式短语。

Tom was too clever a student to be bluffed.汤姆是个很聪明的学生,不会被虚张声势吓倒的。

Be careful not to be beaten up by the enemy.当心别遭敌人暗算。

She doesn't like to make a scene before strangers.当着生人的面,她不愿大吵大闹。

2. 不定式的名词性质表现在：在句中可用作主语或宾语等。

To be content with little is true happiness.知足常乐。

To err is human,to forgive is divine.犯错是人之常情,宽容才是超凡脱俗。

To do drill is important in language learning.做练习对语言学习来说很重要。

He promised to give me a gift.他答应过给我一件礼物。

I would adore to settle back homeland.我非常喜欢回家乡定居。

二、动词不定式在句中的作用

1. 作主语,或在形式主语结构中作真正的主语。

To serve the people is our duty.为人民服务是我们的职责。

It's been lucky to find you.能找到你是一种幸运。

It's very agreeable to have you here.你在这里很令人愉快。

2. 作主语。

The important thing is to save lives.救人要紧。

This police officer's job is to detect fraud.这位警官负责侦查欺诈案。

The drug is to be taken in drops.这种药要一点点地服用。

3. 作宾语,或在形式宾语结构中作真正的宾语。

I hope to see her soon.我希望很快见到她。

Have you decided to marry her?你决定娶她了吗? I thought it wrong to do this thing.我认为做这件事是错的。

I'm preparing to take the examination next week.我在准备下周的考试。

作定语,通常置于其所修饰的名词或代词之后,与其所修饰的名词或代词可能是主谓关系,也可能是动宾关系。

The bus to arrive was from New York.到站的汽车是从纽约开来的。

I have a lot of work to do.我有许多工作要做。

I want to get something to read during the vacation.我想找点书假期看。

Do you have anything more to say?你还有什么话要说吗？

4. 作同位语。

The officer gave the order to stop the attack.军官发出了停止进攻的命令。

He followed the instruction to walk along a certain street where I picked him up.他照吩咐沿某一条街走,我在那里让他搭车。

They had received instructions to watch him.他们收到了监视他的命令。

5. 作目的状语,其逻辑主语通常是全句的主语。

Jack went shopping to buy something.杰克去商店买了一些东西。

I stayed there to see what would happen.我留在那里看看会发生什么事。

They ran over to welcome the delegates.他们跑过去迎接代表们。

6. 作结果状语,其逻辑主语通常也是全句的主语。

The task is too easy to finish.这项任务很容易完成。

What have I done to offend you?我干了什么惹你生气了？

7. 作原因状语,其逻辑主语通常亦是全句的主语。

I'm miserable to hear the message.听到这个消息我很难过。

I trembled to think of it.我一想到那件事就不寒而栗。

8. 作让步状语。

You couldn't do that to help your friends.你即使为了帮你的朋友也不能那样做。

9. 作条件状语。

To look at him you could hardly help laughing.看到他你就会忍不住笑起来。

10. 作宾语补足语,宾语与用作补足语的不定式构成复合宾语,二者在逻辑上是主谓关系。

I'll leave you to look after my house.我将托你照看我的房子。

We believe her to be innocent.我们相信她无罪。

11. 作主语补足语。

Heat is considered to be a form of energy.热被看作是一种能量。

The big building was found to be empty.这座大建筑物被发现是空的。

12. 作独立成分。

To tell the truth,it wasted time to see that film.说实在的,看那样的电影真是浪费时间。

To be specific,the argument in your graduation thesis is logical.具体地说,你的毕业论文符合逻辑。

How time flies,to be sure!时光真是过得快啊!

三、动词不定式的时态与语态

1. 不定式的一般时所表示的动作和状态发生在谓语动词所表示的动作或状态的同时或以后。

He was eager to visit Beijing.他很想游览北京。

I'm glad to see you.我很高兴见到你。

Mother believes her son to be excellent.母亲相信儿子是优秀的。

2. 不定式的进行时所表示的动作或状态与谓语动词所表示的动作或状态同时发生。

Just to be doing something was a help.做点事是有益处的。

Well,it's time to be going to bed.好,是睡觉的时候了。

They seem to be getting along well.他们似乎相处得很好。

3. 不定式的完成时所表示的动作或状态发生在谓语动词所表示的动作或状态以前。

To have known her is a privilege.认识她真是荣幸。

They concluded him to have been dead.他们断定他已死亡。

4. 当不定式的逻辑主语是不定式所表示的动作的承受者时,不定式一般要用被动式。不定式的被动式在句中可用作主语、表语、宾语、定语、状语或补语等。

To be followed was natural to Tom.汤姆生性要别人听命于他。

These books are intended to be read and not to be torn.这些书是供人阅读而不是让人撕毁的。

She asked to be assigned to the research work.她要求被分配从事这项研究工作。

He is a man to be respected.他是一个值得尊敬的人。

He was too young to be assigned such work.他年纪太小,不适宜把这项工作给他做。

She wanted all the invitations to be sent out at once.她要求所有的邀请信立刻发送出去。

四、动词不定式省略to的情况

1. 在助动词或情态动词后接不带to的不定式。

He can speak English and French.他会讲英语和法语。

Must I finish the work today?我今天必须完成这项工作吗?

May I ask you a question?我可以问你一个问题吗？

2. 在had better, had best, would rather, would sooner, rather than等结构后接不带to的不定式。

Doctor had better tell patient the truth.医生最好告诉病人实情。

You'd best not say that.你最好别说那样的话。

I would rather hoe in the garden than run on the playground.我宁愿在花园里锄草,不愿在运动场上跑来跑去。

He would sooner die than surrender.他宁死不屈。

I would rather go shopping than stay.我宁愿去商店也不愿留下来。

3. 在使役动词make,let,have和感官动词see,watch,look at,hear,listen to,feel,smell,observe,notice等词后作宾语补足语时,接不带to的不定式。

You should make him understand this question.你应该让他明白这个问题。

Will you let me know if you can't come to dinner?要是你不能来吃饭,请告诉我好吗？

The soldiers had him stand with his back to his father.士兵们让他背对着他父亲站着。

I saw her face go pale.我看见她的脸变苍白了。

She watched the children play table tennis.她看孩子们打乒乓球。

I thought I heard someone knock on the door.我想我听到有人敲门。

I often listen to the teacher repeat the same topic.我经常听老师重复一个话题。

I didn't notice the car come.我没注意到车来了。

3. 当主语从句中或修饰主语的定语从句中有do时,其表语如是不定式,常省去to。

 “All I did was hit him on the head,” the boy said.“我只是打了他的头,”那男孩说道。

The only thing Jack could do was wait patiently.杰克唯一能做的事就是耐心等待。

4. 在介词but,except之前如有动词do,其后的不定式不用to；其前如无动词do,其后的不定式则一般带to。

Theodore never does anything but talk.西奥多光说不干。

She can do everything except cook.除了不会做饭她什么都能做。

We have no choice but to wait the chance.我们没有选择,只能等待机会。

5. 动词原形go与come等在口语中可接不带to的不定式。

Alexander,come have a glass.亚历山大,来喝一杯吧。

Come and read this book!过来读一下这本书!/Go tell her.去告诉她吧。

6. 为了避免重复而省去to。但两个不定式若有对照或对比之意,则不可省去to。

I'm really puzzled what to think or say.我真不知道该想什么,说什么。

Teacher came not to scold,but to praise you.老师不是来骂你而是来夸你的。

7. 疑问词why引导的省略句中的不定式,在当代英语中一般须省去to。

Why talk so much about it?这样大谈它是为什么?/Why not try again?为什么不再试试呢？