2024届高三英语二轮复习语法专题之情态动词课件(共27张PPT)

(共27张PPT)
Modal Verbs
何为【情态】？
表明说话人的情感和态度， 反应说话人的微妙的心态变化
can /could
may/might
shall/should
must
will/would
have/has to
dare
need
used to
情态动词
表示推测
不表示推测
敢
需要
过去常常
汉 语释 义
ought to
能；请求
可能；请求
应该
将会/应该
必须
将要；请求
不得不
Part One
情态动词表推测
一、must 的用法
1.must 表示推测时， 只能用于肯定句。
e.g. There must be something wrong with the computer.
e.g.You have worked hard all day. You must be tired.
2.must +be doing/do 表示对现在的动作进行肯定推测
e.g.They have bought a new car. They must have a lot of money.
e.g. He must be reading novels now.
3.must +have done 表示对过去发生的事情作出的肯定判断
e.g.They are playing basketball, they must have finished their homework.
must 的易错点（1）
对现在或将来情况推测：must +动词原形。
must只能用于肯定。否定和疑问分别用can’t和can。
e.g. He must tell a lie.
否定句：He can’t tell a lie.
疑问句：Can he tell a lie
must 的易错点（2）
He must be reading, ______ he
You must do it yourself, _______you
He must have gone over the article,_______ he
It must have rained last night, _______ it
表猜测语气的反意疑问句的构成
isn’t
don’t
hasn’t
didn’t
二、can/could 的用法
1. can /could 表示推测时，只能用在否定句或疑问句中。
e.g. It’s so late. Can Tom be reading
e.g. She couldn’t be telling lies.
2. can't/couldn't have done 对过去发生行为的可能性进行推测:
e.g. I saw him just now so he couldn’t have gone abroad.
e.g. She couldn’t have been at home.
3. can/could have done “本可以，本来可能已经”用于肯定句中，表示对过去发生的事情做出的判断.
e.g. You could have had a better mark.
三、may/might 的用法
1.may/might 表示推测时，只能用于陈述句，表示对现在或将来要发生的动作把握不大。
e.g. They may come here tomorrow.
e.g. They may be still waiting for us.
2.might/may have done,表示对过去发生的动作进行可能性推测。
e.g. He may have gone to the clinic.
e.g. He might have read about the news in the newspaper.
表示推测——情态动词的重要用法
肯定的推测
可能的推测
否定的推测
疑问的推测
情态动词
+ V. + V. + have done
常见must be + be doing
+ V. + V. + have done
+ be doing
可以用not表示“可能不”
+V. + V. + have done
+ be doing
+ V. + V. + have done
+ be doing
must
may, might
can’t,
couldn’t
can, could
对将来 对现在 对过去
1. I don't know where she is, she _______ be in Wuhan.
2. At this moment, our teacher ________________our exam papers.
3. The road is wet. It ________________ last night. (rain)
4. Your mother ______________________ for you.
5. Philip ________________________ seriously in the car accident.
Exercise
may
must be marking
must have rained
must have been looking
may (might) have been hurt
6. ---Linda has gone to work, but her bicycle is still here.
　---She _____________________ (go) by bus.
7. Mike ________________ his car, for he came to work by bus
this morning.
Exercise
may (might) have gone
can’t have found
Part Two
情态动词不表推测
1. could(不用can)+have done,在肯定句中表示“本来能够…而没能…”，具有婉转的批评和责备之意。
e.g. I could have passed my exam easily, but I made too many stupid mistakes.
一、情态动词+have done 的四种情况
2. should/ought to+have done用于肯定句时，表示“本该做某事而实际上没做”，用于否定句时，则表示“不该做的事反而做了”
e.g. You should have told him a week ago
e.g. You ought not to have taken the magazine out of the reading room.
3. might（不用may）+have done表示“本来可能…”，但实际上没有发生的事。另外，还可表示“本来应该或可以做某事”之意，含有轻微的责备语气。
一、情态动词+have done 的四种情况
4.用于needn’t +have done表示做了本来不必去做的事。
e.g. She needn’t have gone to the station yesterday.
e.g. You needn’t have bought it.
e.g. You might have come earlier. (事实上你告诉他了)
e.g. You might not have told her.（但没有这样）
Exercise
1.Oh, I’m not feeling well in the stomach. I ____ so much fried chicken just now.
A. shouldn’t eat B. shouldn’t have eaten
C. mustn’t eat D. mustn’t have eaten
2.---Why hasn’t Jane arrived yet
---She ____ again in the morning
A. shouldn’t have overslept
B. may have turned off the alarm clock
C. must have no one to call her
D. should have someone to wake her up
B
B
Exercise
3. ---Did you go to the movie the day before yesterday
----No. We ___, but we decided not to.
A.should have gone B. could go
C. should go D. could have gone
4. As it turned out to be a small house party, we ____ so formally.
A. needn’t dress B. didn’t have to dress up
C. might not have dressed up D. needn’t have dressed up
A
D
二、should 的用法
1. should可表示“居然，竟然”。
e.g. I can’t believe such a gentleman should be so rude to the old.
e.g. Young people should learn how to use computers.
Every citizen ought to obey law.
2. should常表示劝告、建议、命令，与ought to意义相近，但ought to多表示责任、义务，语气强烈。在疑问句中通常用should代替ought to。
二、should 的用法
e.g. You should/ought to have told her the truth earlier.
She shouldn’t have left without saying a word.
3. should/ought to have done 表示责备或批评, 意为“本应该做到…但没有做到…”,用于否定则表示“本不该…但”ought to的语气更强烈.
三、can, could 和be able to的用法
e.g. She can/be able to sing the song in English.
This machine can make you feel comfortable.
1.can, be able to 都可表示“能力”
注：can的主语是人或物,be able to的主语是人
e.g. We’ll be able to finish the work soon.
I haven’t been able to see the film.
2.can只用于现在时和过去时(could)。be able to可以用于各种时态。
三、can, could 和be able to的用法
注：could用于表示泛指过去的能力。
e.g. 1. I could read when I was four.
2. Although the soldier was badly wounded, he was able to tell what had happened.
3. 表示特定的某一过去能力或表示成功地做了某事时，只能用was/were able to， 不能用could。
e.g. He was able to escapefrom Europe before the war broke out.
He was able to swim before he got tired. 　　
四、may 的用法
1. may 表示许可，表示允许别人做某事， 也可征求对方的许可。
e.g. May I open the door
We may keep the book for two weeks.
2. 用于祈使句，表示祝愿。
e.g. May you succeed!
May you have a nice trip!
五、dare & need
情态动词 实义动词
dare 否，疑，条 dare not do 否,疑don’t dare to do 　　　　 don’t dare do
不用于肯定句 肯：dare to do
need 否，疑 needn’t do (don’t) need sth
(don’t) need to do
肯：must, have to, ought to, should
Need I do … Yes, you must.
No, you needn’t.
综合练习（单选）
1.My room is a mess, but I ______ clean it before I go out tonight. I can do it in the morning.
A. daren't B. shouldn't C. needn't D.mustn't
2.---Do you have Betty's phone number
--- Yes, otherwise, I ______ able to reach her yesterday.
A. hadn't seen B. wouldn't have been
C. weren't D. wouldn't be
C
B
综合练习 （改错）
3.“You must put it somewhere else. I am sure it will turn up soon.”
4. We could ask for a better teacher. All our kids love her so much.
must have put
couldn't
综合练习 （填空）
5. It was sad to me that they, so poor themselves, ___________ bring me food.
6. ---________ you interrupt now Can't you see I'm on the phone
--- Sorry Sir, but it's urgent.
should
Must
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