动词不定式的基本形式是“to＋动词原形”，有时可以不带to。动词不定式（或不定式短语）没有人称和数的变化，在句子中不能作谓语。动词不定式仍保留动词的特点，即可以有自己的宾语和状语。动词不定式同它的宾语或状语构成不定式短语。
动词不定式具有名词、形容词和副词的特征，因此在句子中可以作主语、宾语、表语、宾语补足语、定语和状语。
1．作主语
作主语用的动词不定式常常用it替代，动词不定式（或短语）放在后面。例如： It's easy to get lost in a big city like Tokyo．在东京这样的大城市容易迷路。
It is terrible to see the ship sinking into the sea．目睹轮船沉入大海，真是太可怕了。
2．作宾语
Indians like to eat hot food．印度人喜欢吃辣味食品。
They need to look at a map．他们需要查看地图。
有的动词不定式在作带有补足语的宾语时，前面往往带有形式宾语it。例如：
Do you think it necessary for us to learn to wait？你认为学会等待对我们来说很必要吗？
They improved the software to make it easier for people to use computers．他们改进了软件，使人们使用计算机更简便了。
3．作表语
It seems to be an interesting book．它看起来是本有趣的书。
The old man's job is to take care of the flowers in the garden．这位老人的工作是照料花园里的花。
4．作宾语补足语
He told me not to bring you anything．他叫我不要给你带任何东西。
Who taught you to play the music？谁教你弹这支曲子的？
5．作定语
动词不定式作定语时，要放在它所修饰的名词或代词后面。例如：
In my dreams I always have very difficult jobs to do．我在梦里总是做一些艰难的工作。
Every day he made one of the smaller animals bring him something to eat．他每天叫一个小动物给他带来吃的东西。
6．作状语
（1）表示目的
You can hide under my seat when the conductor comes to check the tickets．当列车员来查票时，你可以藏在我的座位下面。
In his third year，he left Harvard to work for a company called Microsoft．在三年级时，他为了去微软公司工作而离开了哈佛大学。
（2）表示结果
动词不定式作状语表示结果时常与副词too或enough连用。例如：
It's too heavy to carry．太重了搬不动。
The Californian ship arrived too late to save more people．加利福尼亚号来得太晚，没能挽救更多的人。
7．和某些形容词连用
和动词不定式经常连用的形容词有sure，ready，happy，sorry，afraid等。例如： He's very happy to see his wife．他见到妻子非常高兴。
I'm sorry to trouble you．很抱歉打扰你了。
8．和疑问词who，what，when，where，which，how构成不定式短语作宾语。例如： I don't know how to use a computer．我不知道怎样使用计算机。
Can you tell
1)不定式做主语一般表示具体的某次动作。
【例如】
TO COMPLETE THE 30STORIED BUILDING IN ONE YEAR WAS QUITE A
DIFFICULT TASK.
TO DO THAT IMPLIES TAKING RESPONSIBILITY.
当主语较长，谓语较短时，常用IT做形式主语，而将不定式放到谓语的后面。
【例如】
IT IS IMPORTANT FOR MODERN YOUNG PEOPLE TO MASTER AT LEAST TWO
FOREIGN LANGUAGES.
IT做形式主语，不定式放在谓语动词之后常用于下列结构中：
A) IT IS＋形容词(EASY, IMPORTANT, DIFFICULT, FOOLISH, INCONVENIENT,
UNNECESSARY, RIGHT, WRONG...)＋( FOR/OF SB.)＋不定式
【例如】
IT IS ESSENTIAL TO RESERVE A TABLE IN ADVANCE OF CHRISTMAS EVE.
IT IS HARD TO PUT MY HOPESSINTOSWORDS.
IT IS NOT EASY TO CATCH FISH WITH YOUR HANDS ONLY.
IT IS IMPORTANT FOR US YOUNG PEOPLE TO LEARN ENGLISH AND MASTER
IT.
B) IT IS＋名词(A PLEASURE, A PITY, A PLEASANT THING, ONE'S DUTY, AN
HONOR, A SHAME, A CRIME, NO EASY JOB...)＋不定式
IT IS A SHEER WASTE OF TIME TO READ THAT KIND OF TRASH.
IT IS A PITY TO HAVE TO GO WITHOUT HER.
IT IS A GLORIOUS DEATH TO DIE FOR THE PEOPLE.
C) IT TAKES (SB.) SOME TIME (HOURS, MONTHS, DAYS, A LOT OF TIME,
PATIENCE...)＋不定式
IT TAKES ME THREE HOURS TO LEARN ENGLISH EACH DAY.
IT TOOK THEM HALF THE NIGHT TO GET HOME IN THE SNOW.
2)不定式作表语不定式作表语常表示将来的动作，主语常常是表示意向、打算、计划
的词，如WISH, IDEA, TASK, PURPOSE, DUTY, JOB等。
【例如】
THE MOST IMPORTANT THING FOR ONE'S HEALTH IS TO HAVE PLENTY OF
EXERCISE.
MY CHIEF PURPOSE HAS BEEN TO POINT OUT THE DIFFICULTIES OF THE
MATTER.
THE PURPOSE OF THE ORGANIZATION IS TO GREET ALL NEW COMERS TO THE CITY AND TO PROVIDE THEM WITH ANY NECESSARY INFORMATION.
WHAT I WANTED WAS TO GET THE WORK DONE AS QUICKLY AS POSSIBLE.
3)不定式作宾语不定式常在下列动词后面作宾语：
AFFORD,AGREE,APPLY,ARRANGE,ASK,ATTEMPT,BEG,BEGIN,CARE,CHOOSE,CL
AIM,CONSENT,DEMAND,DECIDE,DESIRE,DETERMINE,
EXPECT,FAIL,HOPE,HESITATE,HATE,INTEND,LEARN,LIKE,MANAGE,MEAN,NEG
LECT,OFFER,PLAN,PREPARE
PRETEND,PROMISE,REFUSE,RESOLVE,SEEK,TEND,THREATEN,WANT等。
【例如】
I LIKE TO GO OUT FOR WALKS IN THE WARM SUNSHINE IN SPRING.
MY MOTHER HA
不定式在句子中可做主语、宾语、表语、定语、状语和宾语补语。
1)不定式做主语一般表示具体的某次动作。
【例
TO COMPLETE THE 30STORIED BUILDING IN ONE YEAR WAS QUITE A DIFFICULT TASK.
TO DO THAT IMPLIES TAKING RESPONSIBILITY.
当主语较长，谓语较短时，常用IT做形式主语，而将不定式放到谓语的后面。 【例如】
IT IS IMPORTANT FOR MODERN YOUNG PEOPLE TO MASTER AT LEAST TWO FOREIGN LANGUAGES.
IT做形式主语，不定式放在谓语动词之后常用于下列结构中：
A) IT IS＋形容词(EASY, IMPORTANT, DIFFICULT, FOOLISH, INCONVENIENT, UNNECESSARY, RIGHT, WRONG...)＋( FOR/OF SB.)＋不定式
B) IT IS＋名词(A PLEASURE, A PITY, A PLEASANT THING, ONE'S DUTY, AN HONOR, A SHAME, A CRIME, NO EASY JOB...)＋不定式
C) IT TAKES (SB.) SOME TIME (HOURS, MONTHS, DAYS, A LOT OF TIME, PATIENCE...)＋不定式
2)不定式作表语不定式作表语常表示将来的动作，主语常常是表示意向、打算、计划的词，如WISH, IDEA, TASK, PURPOSE, DUTY, JOB等。
【例如】
THE MOST IMPORTANT THING FOR ONE'S HEALTH IS TO HAVE PLENTY OF EXERCISE.
MY CHIEF PURPOSE HAS BEEN TO POINT OUT THE DIFFICULTIES OF THE MATTER.
3)不定式作宾语不定式常在下列动词后面作宾语： AFFORD,AGREE,APPLY,ARRANGE,ASK,ATTEMPT,BEG,BEGIN,CARE,CHOOSE,CLAIM,CONSENT,DEMAND,DECIDE,DESIRE,DETERMINE,
EXPECT,FAIL,HOPE,HESITATE,HATE,INTEND,LEARN,LIKE,MANAGE,MEAN,NEGLECT,OFFER,PLAN,PREPARE
PRETEND,PROMISE,REFUSE,RESOLVE,SEEK,TEND,THREATEN,WANT等。 【例如】
I LIKE TO GO OUT FOR WALKS IN THE WARM SUNSHINE IN SPRING. THE ROOM IS DESIGNED TO BE MY STUDY, BUT NOW IT HAS TO BE USED AS A BEDROOM FOR THE CHILDREN.
THERE IS A MAN AT THE RECEPTION DESK WHO SEEMS VERY ANGRY AND I THINK HE MEANS( )TROUBLE. (CET-4 1997, 1)
A) MAKING
B) TO MAKE
C) TO HAVE MADE
D)SHAVINGSMADE
MEAN后面一般加不定式，所以A和D可以排除。根据句意，他看起来非常生气，他想找麻烦，不定式的动作还没有实施，应用一般式，因此答案为B。
不定式作宾语还常用在下面结构中；主语＋动词＋IT＋形容词＋不定式。
【例如】 WE FOUND IT IMPOSSIBLE TO GET EVERYTHING READY IN TIME. I THINK IT IMPORTANT TO LEARN ENGLISH WELL IN COLLEGE.
使用这种句型的常见动词有：BELIEVE, CONSIDER, DECLARE, FEEL, FIND, GUESS, IMAGINE, PROVE, REALIZE, SUPPOSE, THINK,等。
4)“WHWORD＋不定式”结构不定式前加一个疑问代词(WHAT, WHICH, WHO, WHOM, WHOSE)或疑问副词(WHERE, WHEN, HOW, WHY)，以及连词WHETH
动词不定式的基本形式是“to＋动词原形”，有时可以不带to。动词不定式（或不定式短语）没有人称和数的变化，在句子中不能作谓语。动词不定式仍保留动词的特点，即可以有自己的宾语和状语。动词不定式同它的宾语或状语构成不定式短语。
动词不定式具有名词、形容词和副词的特征，因此在句子中可以作主语、宾语、表语、宾语补足语、定语和状语。
1．作主语
作主语用的动词不定式常常用it替代，动词不定式（或短语）放在后面。例如： It's easy to get lost in a big city like Tokyo．在东京这样的大城市容易迷路。
It is terrible to see the ship sinking into the sea．目睹轮船沉入大海，真是太可怕了。
2．作宾语
Indians like to eat hot food．印度人喜欢吃辣味食品。
They need to look at a map．他们需要查看地图。
有的动词不定式在作带有补足语的宾语时，前面往往带有形式宾语it。例如：
Do you think it necessary for us to learn to wait？你认为学会等待对我们来说很必要吗？
They improved the software to make it easier for people to use computers．他们改进了软件，使人们使用计算机更简便了。
3．作表语
It seems to be an interesting book．它看起来是本有趣的书。
The old man's job is to take care of the flowers in the garden．这位老人的工作是照料花园里的花。
4．作宾语补足语
He told me not to bring you anything．他叫我不要给你带任何东西。
Who taught you to play the music？谁教你弹这支曲子的？
5．作定语
动词不定式作定语时，要放在它所修饰的名词或代词后面。例如：
In my dreams I always have very difficult jobs to do．我在梦里总是做一些艰难的工作。
Every day he made one of the smaller animals bring him something to eat．他每天叫一个小动物给他带来吃的东西。
6．作状语
（1）表示目的
You can hide under my seat when the conductor comes to check the tickets．当列车员来查票时，你可以藏在我的座位下面。
In his third year，he left Harvard to work for a company called Microsoft．在三年级时，他为了去微软公司工作而离开了哈佛大学。
（2）表示结果
动词不定式作状语表示结果时常与副词too或enough连用。例如：
It's too heavy to carry．太重了搬不动。
The Californian ship arrived too late to save more people．加利福尼亚号来得太晚，没能挽救更多的人。
7．和某些形容词连用
和动词不定式经常连用的形容词有sure，ready，happy，sorry，afraid等。例如： He's very happy to see his wife．他见到妻子非常高兴。
I'm sorry to trouble you．很抱歉打扰你了。
8．和疑问词who，what，when，where，which，how构成不定式短语作宾语。例如： I don't know how to use a computer．我不知道怎样使用计算机。
Can you tell
1)不定式做主语一般表示具体的某次动作。
【例如】
TO COMPLETE THE 30STORIED BUILDING IN ONE YEAR WAS QUITE A
DIFFICULT TASK.
TO DO THAT IMPLIES TAKING RESPONSIBILITY.
当主语较长，谓语较短时，常用IT做形式主语，而将不定式放到谓语的后面。
【例如】
IT IS IMPORTANT FOR MODERN YOUNG PEOPLE TO MASTER AT LEAST TWO
FOREIGN LANGUAGES.
IT做形式主语，不定式放在谓语动词之后常用于下列结构中：
A) IT IS＋形容词(EASY, IMPORTANT, DIFFICULT, FOOLISH, INCONVENIENT,
UNNECESSARY, RIGHT, WRONG...)＋( FOR/OF SB.)＋不定式
【例如】
IT IS ESSENTIAL TO RESERVE A TABLE IN ADVANCE OF CHRISTMAS EVE.
IT IS HARD TO PUT MY HOPESSINTOSWORDS.
IT IS NOT EASY TO CATCH FISH WITH YOUR HANDS ONLY.
IT IS IMPORTANT FOR US YOUNG PEOPLE TO LEARN ENGLISH AND MASTER
IT.
B) IT IS＋名词(A PLEASURE, A PITY, A PLEASANT THING, ONE'S DUTY, AN
HONOR, A SHAME, A CRIME, NO EASY JOB...)＋不定式
IT IS A SHEER WASTE OF TIME TO READ THAT KIND OF TRASH.
IT IS A PITY TO HAVE TO GO WITHOUT HER.
IT IS A GLORIOUS DEATH TO DIE FOR THE PEOPLE.
C) IT TAKES (SB.) SOME TIME (HOURS, MONTHS, DAYS, A LOT OF TIME,
PATIENCE...)＋不定式
IT TAKES ME THREE HOURS TO LEARN ENGLISH EACH DAY.
IT TOOK THEM HALF THE NIGHT TO GET HOME IN THE SNOW.
2)不定式作表语不定式作表语常表示将来的动作，主语常常是表示意向、打算、计划
的词，如WISH, IDEA, TASK, PURPOSE, DUTY, JOB等。
【例如】
THE MOST IMPORTANT THING FOR ONE'S HEALTH IS TO HAVE PLENTY OF
EXERCISE.
MY CHIEF PURPOSE HAS BEEN TO POINT OUT THE DIFFICULTIES OF THE
MATTER.
THE PURPOSE OF THE ORGANIZATION IS TO GREET ALL NEW COMERS TO THE CITY AND TO PROVIDE THEM WITH ANY NECESSARY INFORMATION.
WHAT I WANTED WAS TO GET THE WORK DONE AS QUICKLY AS POSSIBLE.
3)不定式作宾语不定式常在下列动词后面作宾语：
AFFORD,AGREE,APPLY,ARRANGE,ASK,ATTEMPT,BEG,BEGIN,CARE,CHOOSE,CL
AIM,CONSENT,DEMAND,DECIDE,DESIRE,DETERMINE,
EXPECT,FAIL,HOPE,HESITATE,HATE,INTEND,LEARN,LIKE,MANAGE,MEAN,NEG
LECT,OFFER,PLAN,PREPARE
PRETEND,PROMISE,REFUSE,RESOLVE,SEEK,TEND,THREATEN,WANT等。
【例如】
I LIKE TO GO OUT FOR WALKS IN THE WARM SUNSHINE IN SPRING.
MY MOTHER HA
不定式在句子中可做主语、宾语、表语、定语、状语和宾语补语。
1)不定式做主语一般表示具体的某次动作。
【例
TO COMPLETE THE 30STORIED BUILDING IN ONE YEAR WAS QUITE A DIFFICULT TASK.
TO DO THAT IMPLIES TAKING RESPONSIBILITY.
当主语较长，谓语较短时，常用IT做形式主语，而将不定式放到谓语的后面。 【例如】
IT IS IMPORTANT FOR MODERN YOUNG PEOPLE TO MASTER AT LEAST TWO FOREIGN LANGUAGES.
IT做形式主语，不定式放在谓语动词之后常用于下列结构中：
A) IT IS＋形容词(EASY, IMPORTANT, DIFFICULT, FOOLISH, INCONVENIENT, UNNECESSARY, RIGHT, WRONG...)＋( FOR/OF SB.)＋不定式
B) IT IS＋名词(A PLEASURE, A PITY, A PLEASANT THING, ONE'S DUTY, AN HONOR, A SHAME, A CRIME, NO EASY JOB...)＋不定式
C) IT TAKES (SB.) SOME TIME (HOURS, MONTHS, DAYS, A LOT OF TIME, PATIENCE...)＋不定式
2)不定式作表语不定式作表语常表示将来的动作，主语常常是表示意向、打算、计划的词，如WISH, IDEA, TASK, PURPOSE, DUTY, JOB等。
【例如】
THE MOST IMPORTANT THING FOR ONE'S HEALTH IS TO HAVE PLENTY OF EXERCISE.
MY CHIEF PURPOSE HAS BEEN TO POINT OUT THE DIFFICULTIES OF THE MATTER.
3)不定式作宾语不定式常在下列动词后面作宾语： AFFORD,AGREE,APPLY,ARRANGE,ASK,ATTEMPT,BEG,BEGIN,CARE,CHOOSE,CLAIM,CONSENT,DEMAND,DECIDE,DESIRE,DETERMINE,
EXPECT,FAIL,HOPE,HESITATE,HATE,INTEND,LEARN,LIKE,MANAGE,MEAN,NEGLECT,OFFER,PLAN,PREPARE
PRETEND,PROMISE,REFUSE,RESOLVE,SEEK,TEND,THREATEN,WANT等。 【例如】
I LIKE TO GO OUT FOR WALKS IN THE WARM SUNSHINE IN SPRING. THE ROOM IS DESIGNED TO BE MY STUDY, BUT NOW IT HAS TO BE USED AS A BEDROOM FOR THE CHILDREN.
THERE IS A MAN AT THE RECEPTION DESK WHO SEEMS VERY ANGRY AND I THINK HE MEANS( )TROUBLE. (CET-4 1997, 1)
A) MAKING
B) TO MAKE
C) TO HAVE MADE
D)SHAVINGSMADE
MEAN后面一般加不定式，所以A和D可以排除。根据句意，他看起来非常生气，他想找麻烦，不定式的动作还没有实施，应用一般式，因此答案为B。
不定式作宾语还常用在下面结构中；主语＋动词＋IT＋形容词＋不定式。
【例如】 WE FOUND IT IMPOSSIBLE TO GET EVERYTHING READY IN TIME. I THINK IT IMPORTANT TO LEARN ENGLISH WELL IN COLLEGE.
使用这种句型的常见动词有：BELIEVE, CONSIDER, DECLARE, FEEL, FIND, GUESS, IMAGINE, PROVE, REALIZE, SUPPOSE, THINK,等。
4)“WHWORD＋不定式”结构不定式前加一个疑问代词(WHAT, WHICH, WHO, WHOM, WHOSE)或疑问副词(WHERE, WHEN, HOW, WHY)，以及连词WHETH