情态动词用法总结及相应练习

情态动词用法总结及相应练习在英语中，情态动词属于助动词。

除了作简略回答外，它们一般不能单独使用，它们必须与动词原形一起使用构成句子的谓语。

不同的情态动词会有不同的意义和用法。

有时，同一个情态动词在不同的语境中也会产生不同的含义。

下面我们将讨论这些情态动词的用法。

情态动词的推测性用法和非推测性用法
情态动词一般有两种用法：推测性用法(epistemic use)和非推测性用法(non-epistemic use)。

推测性用法是指做出推测,预测事物发生的可能性;非推测性用法则指情态动词本身的基本含义，如XXX表示能力，may表示许可，must和should表示必须和义务，need 表示需要等。

例如：
I can swim。

(非推测性用法)
This can be true。

(推测性用法)
You may go now。

(非推测性用法)
He may be ill now。

(推测性用法)
You must finish it before lunch time。

(非猜测性用法)
He must be at home for he never goes out at dinner time。

(推测性用法)
我们把英语中的9大神态动词按其猜测性和非猜测性用法列表如下:
情态动词非推测性用法推测性用法
can／could能力/许可(ability／n)可能(possibility)
may／might许可(n)可能(possibility)
will／would意愿(n)预言性(predictability)
XXX责任和义务(n)应该是(logical necessity)
must责任和任务(n)一定,一定(logical necessity)
神态动词非猜测性用法的申明
1.may和might透露表现允许
may能够与分歧的人称搭配，透露表现“答应、允许”。

比方：
May I know your name?
You may be the first to leave if you are in a hurry。

(我允许你第一个离开。

)
You may keep the book for two months。

(我允许你借。

)
XXX may ask a driver to take a breath test.
may用在疑问句中，经常表示“允许、许可”的意思。

例如：
May I know your name?
May I XXX?
might能够用来透露表现曩昔时态，也能够透露表现婉转语气。

比方:
She said that he might take her nary。

(may的曩昔式)
Might I have a word with you。

(婉转用法)
I wonder if I might have more salad。

(委婉用法)
但在回覆中，我们一般用may增强一定的语气，而不消might.比方：
Yes。

of course you may.
may not可用来表示“禁止”或“不许”，因语气较强，所以不用might not.例如：
XXX.
must not也可以表示“禁止”，而且语气比may not更强，强调上级对下级的不允许。

另外，may/might as well也是一个常用的词组，后接动词原形，意思是“不妨，最好”
相当于had better.例如：
It's very late。

We might as well go home.
2.can和could
1)透露表现本领
can,could和be able to都能够透露表现本领。

但若要透露表目前曩昔某个详细场所下能够做某事的本领，我们用was/were able to.比方：
Thank you for your help.
I‘m glad I was able to help you。

(在这种情形下能够帮你，并且曾经帮了。

)
所以was/were able to不仅表示过去的某个具体场合下的能力，还强调动作已经成功完成，相当于manageto do或succeed in doing.例如：
We were able to save him。

(把他救活了。

)
He was able to explain what had XXX。

(他能申明，并且也申明了。

)
He could explain what had XXX。

(他能做出解释，但可能没有说。

)
但这种区别只局限在陈述句，在否定句中，be able to和could可以互换。

有时，could表示的并不是XXX的过去式，而是一种委婉的语气。

例如：
Could you run the business yourself?
I could give you a chance.
Could you please give me your reply as soon as possible?
could have done有虚拟的含义，即“本来能够做，但事实上却没有做”。

例如：
XXX.
I could have helped her.
I could have passed the exam if I had worked harder.
2)透露表现答应
can也可以用来表示“允许”，例如：
Can I smoke here?
XXX.
XXX says we can't park our car here.
could可以使句子更显礼貌，但在肯定回答中，我们一般用can代替could,加强肯定的语气。

即：Yes。

of course you can.
3)其他用法
can not与help。

bear。

stand等动词连用，透露表现“禁不住，受不了”。

例如：
If one had talent。

one can't help showing it.
I can't stand waiting any longer.
但是can’t help but后面接动词原形，表示“只能”。

I ca n not help but askyou: “do you have loved me?”
I can’t help but wait.
3.must表示必须
must的这种用法，表现了语言者的权势巨子性，以是must通经常利用于上级对上级、尊长对小辈。

比方:
You must be back by ten o'clock.
XXX: XXX.
注意］must和have to的区别：must表示出于说话者本人的主观愿望，必须去做某事；而have to表示受外部条件的影响，不得不做某事。

比方：
I must leave now。

(我自己想离开，主观愿望。

)
I have to leave now。

(也许我还想坐一会儿，但我有要事，不得不走了。

)
He must say it in English。

(除了英语，他可能还懂其他语言，但我的主观愿望是他必须说英语。

)He has to say it in English。

(客观条件是他只懂英语，所以不得不用英语说。

)
别的，因为must没有未来时态，以是我们通经常利用XXX来透露表现；因为must没有曩昔时态，以是我们通经常利用had to来透露表现。

例如：
We will have to do it again.
I had to leave at 6:30 yesterday.
但偶然，我们也能够在透露表现曩昔的高低文中利用must.
例如：
I told him that he must mind his own business.
must有两种否认方式：mustn't和XXX.
XXX表示"不可以“，XXX表示“不必”。

比方：
XXX。

(不能够= XXX.)
Must you leave so soon?
No。

I XXX't.
4.should和XXX
should和XXX平日能够交互利用，意义没有多大的区别，透露表现“应当”。

should和oughtto的这种用法平日透露表现“建议、催促或煽动”。

比力］must。

have to和XXX所透露表现的分歧语气：
钢琴老师对某学生说：
XXX an hour a day。

(must显示了老师的权威。

)
这个学生然后对他的朋友说：
I have to practice an hour a day。

(have to透露表现我自己不想练，但迫于教师的压力，不能不练。

)他的同伙会说：XXX for more than an hour。

(表示不是来自外界的权威或压力，而是来自平辈同学或朋友的建议：如要做个好学生，弹好钢琴。

)
别的，should have done／ought to have done透露表现“本该产生的事没有产生；
例如：
You should have told me earlier.
You ought to have been more careful.
5.will和would
will和would作情态动词使用，主要有以下的用法：
1)表示意愿
will和would透露表现的志愿可强可弱，志愿弱时透露表现“XXX做某事”(willingness);志愿强时透露表现“坚持要做某事”(insistence).比方：
Will you go with us?(愿意)
Will you pass me the salt。

(乐意)
Let us have a talk。

will you。

(乐意)
I will marry her XXX.(表示坚持)
would可以表示“过去的愿意”，一般用于间接引语中，例如:He said he would come.
在其他情况下，would不表示过去，而表示"委婉的语气“，例如：
Would you please make a copy for me?
但在回覆中，为了增强一定的语气，我们用will.比方：
Would you let me hear from you soon?
Yes。

I will.
2)表示能力、趋势或必然性
will和would的这种用法一般以工具作为主语，透露表现“其内涵的机能或特性性偏向”。

比方：
Oil will float on water.
Gold XXX.
否定形式XXX还可以表示“某事没有达到我们期望的效果”。

例如：
The car XXX start.
XXX.
注意］这里用主动语态。

3)透露表现气性的举措。

比方:
Every morning he will sit in the office doing nothing.
He will often say something and then et it.
在这种用法中，would是will的过去式。

例如：
He would never let anybody know what he was doing.
In those days he would work day and night。

with no time to care for his children.
6.shall
shall通常有以下用法：
1)表示“说话者的决心或承诺”。

比方：
I shall never give up.
XXX XXX.
You shall get your salary tomorrow。

(I promise。

)
He shall get his share。

(I promise。

)
You shall stay with us as long as you like。

(I promise。

)
2)透露表现“敕令”，语气很强。

例如：
You shall go at once.
You shall do as I say.
You shall never tell lies.
此种语气因太专横，所以一般不用，但在法律文件和合同条款中，我们通常用shall表示权利和义务。

例如：
Party A shall advise Party XXX any n that comes to Party A's n。

Party A shall。

within 14 days of receipt of a written request by Party B。

deliver to Party B a written report on
Party A's activities。

Party A shall be an independent XXX.
3)疑问句中用来征求意见。

比方：
Shall I pick you up at six。

(Do you want me to pick you up at six?)
XXX?
Shall he go on an errand。

(Do you want him to go on an errand?)
Let's have a rest。

shall we?
7.need
need可以作行为动词，也可以作情态动词。

need 作行为动词时，有时态的变化，后面跟动词不定式或名词，其否定式和疑问式要用助动词；need作情态动词时，后面只跟动词原形，其否定式和疑问式不用助动词，而是直接在need后面加上not构成否定式，疑问句直接把need提前。

比方：
XXX't come。

(神态动词)
I wonder if we need take XXX(神态动词)
I need your help。

(行为动词)
I need to have a look。

(行为动词)
Need we work today。

(情态动词)
Yes。

we must。

(No。

we needn't.)
need作情态动词，表示“需要”，常用在否定句、疑问句或if引导的从句中，在回答need引导的问句中，肯定回答用must加强语气，表示“必须”；否定回答用needn‘t,表示“不必”，
相当于not have to.Needn‘t hav e done表示“没有做某事的必要，该事本不必做，但却做了”；XXX只是表示“不必做某事，而且该事也确实没有做”。

例如：
I XXX't need to go to the XXX(没有去车站)I needn't have gone to the XXX(去了车站)
8.dare
dare可以作行为动词，也可以作情态动词。

dare 作行为动词时，有时态的变化，后面跟动词不定式，其否定式和疑问式要用助动词；dare作情态动词时，后面只跟动词原形，其否定式和疑问式不用助动词，而是直接在dare后面加上not构成否定式，疑问句直接把dare提前。

例如：
I wonder how she dared to say that。

(行为动词)
XXX't dare to play with you。

(行为动词)
Does she dare to go there alone。

(行为动词)
Dare you jump over the ditch。

(情态动词)
She dare not go out at night。

(情态动词)
I dared not tell him the bad news。

(情态动词)
9.had better
had better的意思是“最好”，表示建议，相当于It‘s better for you to。

had better后跟省略了to的动词不定式，即had better do;其否定式为had better not do,表示“最好不”。

比方：
We had better start now.
You had better not take the risk.
神态动词的猜测性用法
用于猜测性含义时，might可能性最小，must可能性最大。

1.may和might透露表现可能性
表示“可能性比较大”时，我们用may；如果可能性比较小，我们用might。

例如：
He might tell his friends。

(可能性小)
He might be waiting at the gate.(可能性小)
He may be at home。

(可能性大)
Tom may lend you the bike。

(可能性大= It is very XXX。

) Tom might lend you the bike.(可能性小= I think it is unlikely.)
might也可以表示“过去的可能性”。

例如：If you invited him，he might come.
若要表示“不可能”，我们用can’t或couldn’t。

比方：
He can’t be the manager。

He is only a r clerk.
在问句中，may只能用来表示“允许”，不能表示可能性；否则，我们用can。

do you think。

is it likely that,is it possible that等结构来表示可能。

例如：
May I come in。

(表示许可)
Yes。

come in please.
Where can he be。

(表示可能性)
He may be in the office.
may可与have done连用，构成may have done,表示“某一事件在过去发生的可能性”。

比方：
Why hasn’t she come?
She may have missed the train.
He isn’t back yet。

He may have had an accident.
另外，might have done还有虚拟的含义，表示“与事实相反”。

例如：
You were stupid to try climbing up there。

You might have killed yourself.
2.can和could表示可能性
can和could可以表示“事物实际发生的可能性”。

如果逻辑判断是现在或说话时刻作出的，用can\could 用来判断可能性，不确定性和委婉的语气要更强一些。

例如：
Can／Could the news be true?
If you don’t have a guide。

you could lose your way.
另外，XXX的这种用法多出现在否定句中，表示“不可能”。

比方：
It can’t／couldn’t be true.
The moon can’t always be at the full.
XXX.
can not have done透露表现“曩昔的工夫产生的可能性很小”。

比方：
The door can’t have been open for I locked it myself.
3.must表示极大的可能性
must的此种用法，指的是逻辑上较大的可能性，表示“一定\肯定”,比will和should语气更强。

例如：
You must be mad to do that。

(干那事你一定是疯了。

)
must透露表现“猜测”，平日只用于一定方式，其否认方式为can’t。

例如:
You must have difficulty getting the tickets.
You can’t have XXX.
对过去动作的推测通常用must have done来表示，否定形式是can’t have done。

XXX.
You can’t have left your XXX.
I don’tthink he can have heard you。

Call again.
1)—Can I have some sweets。

I am hungry.
You can’t be hungry。

You’ve just had XXX.
2)—A man XXX it was her husband.
It can’t have been her husband。

He has been dead for ages.
must透露表现猜测的可能性比may的可能性大很多。

比力：
1)钥匙圈上有三把钥匙，其中一把是开房门的。

当我们拿起其中一把时，我们说：This may／might be thekey。

(当试了两把钥匙门都没有开后，我们拿起第三把钥匙。

)这时我们说: This must be the key。

(因为这是最后一把钥匙了。

)
2)看上面的对话：
I XXX.
He might be ill。

(他可能病了，但也有其他的可能，如他太忙了，等等。

)
4.should和ought to透露表现极大可能性
should和ought to的这种用法指通过逻辑推断得出的极大可能，可以理解为“应该是”(= It XXX。

).
例如：
That should not be a difficult problem for Kate。

(不该当是个困难。

)
It should be ten o’clock now.
5.will和would表示预言
在这种用法中，will／would表示“情况肯定会是这样”。

但would的可能性比will小。

比方：
1)—Where is Tom?
He will be in the library.
2)—There is XXX.
It will be Mary.
比较will和should在推测性用法中语气的差异：
Tom should know the address。

(我想XXX应该知道= I expect Tom knows it.)
Tom will know the address。

(我肯定XXX会知道的= I am sure Tom knows it.)
从以上的例子中不好看出，will用来透露表现“猜测”时，语气比should愈加一定。

别的，should透露表现“猜测”不克不及用于贬义的(或使人感触不悦的)语境中。

例如：
Let’s not go shopping now。

The shops will be very crowded。

(这里不克不及用should)
Let’s go shopping now。

The shops will/should be fairly empty。

(这里也可以用ought to)
练题：
1) You____ all those clothes。

We have a washing machine to do that sort of thing
A) needn't have washedB) shouldn't have washed
C) must not have washedD) can not have washed
2) John's score on the test is the highest in the class。

he____ last night.
A) should studyB) should have studied
C) must have studiedD) must have to study
3) The room is in a terrible mess。

it ____cleaned。

(CET-
4.1996,6)
A) can't have beenB) shouldn't have been
C) mustn't have beenD) wouldn't have been
4) Nobody knows how people first came to these XXX ____ XXX) must have sailedB) can sail
C) might have sailedD) should have sailed
5) Mary was not in her XXX ____ in her classroom.
A) should have beenB) must have been
C) must beD) should be
6) Bob said he was going to join our club but he didn't。

He ____ his mind.
A) can't have changedB) wouldn't have changed
C) must have changedD) shouldn't have changed
7) You____ to town to see the film yesterday。

It will be on TV tonight.
A) needn't goB) had better not go
C) should not goD) needn't have gone
8) We____ XXX。

but it didn't arrive.
A) must receiveB) XXX receive
C) must have receivedD) ought to have received
9) With all the work on hand。

he____ to the cinema last night.
A) mustn‘t goB) shouldn’t have gone
C) could not goD) couldn't have gone
10) XXX ____ earlier.
A) should get upB) must get up
C) need to get upD) should have got up
11) I am feeling sick。

I____ so much chocolate.
A) needn't have eaten B) couldn't have XXX
C) mustn't have eatenD) shouldn't have XXX
12) I didn't send out my n form last week。

but I ____.
A) hadB) would do
C) should haveD) might have to
1.--- _____ I go out to play now。

Mum?
No。

you _____。

You should do your homework first.
A。

Must。

XXX。

wouldn’t
C。

May。

needn’tD。

May。

had better not
2._____ you like to have a walk with us this evening?
A。

XXX
3.You _____ be careful when you cross here --- the traffic XXX.
A。

could B。

mightC。

ought toD。

may
4.We were all waiting for you。

you _____ for the XXX.
A。

XXX
XXX’t have left
5.It _____ be she that told him about it。

it _____ be you。

because only you and I know it.
A。

mustn’t。

XXX’t。

must
C。

mustn’t。

XXX’t。

might
6.A hardworking man _____ e a great scientist。

but a great scientist _____ be a hardworking man.A。

can’t。

can B。

may not。

can
C。

can’t。

mustD。

may not。

must
7.You _____ go right now if you want。

but I think you _____。

because we have XXX.
A。

must。

may not B。

must。

can’t
C。

may。

needn’tD。

may。

mustn’t
8.--- Why do you ask me to do the difficult work?
Because you _____ do such a thing and nobody else is fit for it.
A。

XXX。

should D。

may
9.You _____ be tired。

you have been working for so long a time。

but he _____ be tired。

he has just begun to work.
A。

may not。

must B。

must。

may not
C。

can’t。

mustD。

must。

can’t
10.It’s said that there are plenty of hotels in that town。

There _____ be XXX.
A。

XXX’t
C。

XXX’XXX’t
11.Don’t believe him。

What he said ______ be true.
A。

XXX’t B。

XXX’t
C。

XXX’tD。

may not
12.--- Must I take a bus?
No。

you _____。

You can walk there.
A。

must not B。

may not
C。

don’t have toD。

had better not to
13.--- Do you think he will help me?
As far as I know。

he is the last one to help others。

He _____ be prepared to give you a hand。

though.
A。

XXX
14.You _____ return the nary now。

You can keep it till next week if you like.
A。

can’t B。

mustn’t
XXX
15.The thief _____ in from the kitchen window as all the other windows and doors were closed.
A。

may climbB。

must have climbed
C。

could climb D。

should have climbed
16.--- We want someone to design the new art museum for us.
______ the young fellow have a try?
A。

XXX
17.--- Must we do it now?
No。

you _______.
A。

XXX’t
18.---I don’t know why he is late.
Nor do I。

He _____ an accident.
A。

could have had B。

should have had
C。

might have hadD。

must have had
19.I got up early。

but I _____ so because I had no work to do that morning.
A。

XXX done
C。

needn’t have done D。

can’t have done
20.--- ______ he use your bike？
Certainly。

Here is the key.
Certainly。

Here is the key.。