(共26张PPT)
情态动词表推测
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Lead in
CONTENTS
01. 理解掌握表推测的情态动词
02. 学会运用表推测的情态动词
教学目标：
表能力/推测
表请求许可
表建议/责任
表劝告/建议
表需求看法
表义务/推测
表请求/意愿
表需要
can/
could
may/
might
must/
have to
shall/
should
need
will/
would
had better
ought to
01. can/could
表示能力(=be able to)
(否定句中)表可能性
(疑问句中)表请求许可
02. may/might
表示请求许可
(肯定句中)表把握不打的推测
05. must/have to
have to表示客观需要，意为“不得不”
must表示主观看法，意为“必须”；还可表肯定的推测
03. shall/should
shall用于第一，三人称，表示建议或请求；
should表示建议或责任（=ought to）
08. need
need作实义动词，表“需要”
need作情态动词，用于否定句和疑问句中
07. will/would
will表询问，请求或者表达意思；
would表请求别人做某事
04. had better
表劝告或建议
否定形式：had better not
06. ought to
表义务，意为“应该”
（表责任义务等该做），
语气比should稍重；
表推测，暗示很大的可能，语气较弱。
Let's review
考点
情态动词 肯定式 否定式 疑问式
必定；必然 / /
/ 不可能 有可能吗
微弱的可能 / 有可能吗
或许；也许 可能不 /
可能 可能不 /
must
can
could
may
might
情态动词的推测用法
(以下情态动词对可能性的推测排列顺序由强到弱)
情态动词表推测
肯定用法
例句
非常有把握的肯定推测用must，意为“一定，肯定”。
It must be raining outside.Her clothes are so wet.外面一定在下雨，她的衣服太湿了。
表示把握不大的肯定推测用may，意为“有可能，也许”。
It may be Nancy's pen. 它可能是南希的钢笔。
情态动词表推测
肯定用法
例句
如果可能性稍低于may，用might“有可能，也许”。
The ball might be Lily's. I'm not sure.
这个球可能是丽丽的，我不确定。
肯定句中语气最弱的推测“可能”，用could.
I would go if I could.
能去我就去。
情态动词表推测
否定用法
例句
否定句中语气较弱，用may not，意为“可能不”。
The characters may not be perfect, but they try their best to solve their problems.
否定句中语气强，可能性几乎为零，用can't，意为“一定不，不可能”。
Miss Wang can't be in Japan. I just saw her in the supermarket.
1．There__________ be something wrong with my mobile phone. It can't work these days.
2．He__________in his office, but I'm not sure.
3．You____________like her, but you cannot ignore（忽视） her.
4．Jack walked here today, so this bike__________be his.
Let's practice
can't
must
might
may not
must
might
may not
can't
防坑指南
1.表示允许时，may和might比can和could正式。May I…？句式的肯定回答用Yes，you can/may.等；否定回答用No，you can't./No，you mustn't..
2.表示不允许时，以must开头的一般疑问句的否定回答常用needn't 或don't have to 来回答。
3.表推测时，语气must>can>
could>may>
might。
Let's practice
A
1. Jenny finally got the job because she
______ speak English well.
A. might
B. must
C. could
A
B
B
C
C
C
NEXT
Let's practice
A
2. It's surprising that Mr. Ma's little daughter
______ speak English so well.
A. must
B. can
C. mustn't
A
C
C
B
B
B
NEXT
Let's practice
A
3. Cars, buses, bikes and people ______ stop when the traffic lights are red.
A. can
B. may
C. must
A
B
B
C
C
C
NEXT
Let's practice
4. —Must I finish all the homework this evening
—No, you ______. Tomorrow is Saturday, and you have enough time for it.
A. mustn't B. needn't
C. won't D. can't
A
B
D
C
Let's practice
5. A: Mum, may I go out to play football for an hour
B: No, you ______. The air outside is not very clean.
A. can't B. needn't
C. couldn't D.mustn't
B
A
D
C
Let's practice
6. —Must I hand in the exercise book today, Miss Green？
—No, you ______. Take your time. Just tomorrow.
A. shouldn't B. don’t have to
C. mustn't D. can't
A
C
B
D
Let's practice
7. —Can you come to my party on Wednesday
—Sorry, I ______. I have a piano lesson.
A. can't B. couldn't
C. mustn't D.needn't
B
A
D
C
START
侦探真题大冒险
1
2
3
1. You are not allowed to play with fire in the forest. It _______ kill plants, animals and even people. (2020云南昆明)
A. might B. might not C. should D. should not
A
A
B
C
D
A
侦探真题大冒险
1
2
3
闯关成功
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NEXT
2. —Must I hand in the report now, sir
—________ .You can hand it in tomorrow. (2020广西百色)
A. Yes, you can B. Yes, you must
C. No, you needn’t D. No, you mustn’t
C
C
B
A
D
C
侦探真题大冒险
1
2
3
闯关成功
获得 1把
NEXT
3.You _______ take photos here!Look at the sign. It says “No photos”. (2021.云南)
A. must B. need C. mustn't D. needn’t
C
C
B
A
D
C
侦探真题大冒险
1
2
3
闯关成功
获得 1把
NEXT
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1.情态动词表推测
表肯定推测: must>can>could>may>might.
表否定推测：can’t >may not.
Let's sum up
2.May I…？句式的肯定回答用Yes，you can/may.等；
否定回答用No，you can't./No，you mustn't.
3.以must开头的一般疑问句的否定回答常用needn't 或don't have to 来回答。
THANK YOU
Thank you
