must 的用法
1.must 表示主观上的必须，应该，没有时态 变化。
You must do everything as I do.
注意:
—Must I finish my homework today?
— Yes, you must. — No, you needn’t. / No, you don’t have to.
He said I could borrow his bike.
Could I use your bike?
— Could I borrow your dictionary? — Yes, of course you ____． A. might B. will C. can D. should
3.表“可能性”
can ,could 用在肯定句中表示理论上的可能性， “经验之谈”
As a human being, anyone can make a mistake. can ,could用在疑问句中表推测,表示可能性
Can she be in the classroom? can ,could用在否定句中表推测，翻译成“不 可能 ” We thought the story couldn’t be true.
A. No, you needn’t B. Not, please. C. No, you mustn’t D. No, you won’t
注意：
may I …? 的答语. 肯定: Yes, you may . 否定: No, you mustn’t (语气强硬)
No, you may not. 或 No, you’d better not.
1. 1I. ccaann/ a表m示a现ble在to的sw能im力. 2. 2.I ccoouli力mb a tree when I was a
child. 3. be able to 表能力，可用于多种时态 3. I will be able to swim next week.
4. 4.Tbhee fairbelesptorea强d调th成ro功ug地h t做he了h某ote事l very quickly but everyone was able to get out.
2.表“请求,许可” could用来表示请求的时候比can 更委婉
Can you help me with my English?
高中英语情态动词详解(强推)
The features（特点) of the modal verbs:
1. 情态动词本身有词义, 但词义不完全. 2. 不能单独作谓语,只能和动词原形一起构成谓语. 3. 情态动词没有人称和数的变化( 除“have to”).
4H.e没ca有n不/co定ul式d/、mVus-itn/mga、y/Vm-eigdh形t/s式ha.ll/ should/need/dare/dared/will/would/ought to/ used to + work in that factory.
may与might用法
1.表“询问” (might比用may更客气.) May I …? (=Can I … ?) Might I … ? (=Could I … ?) May I borrow your book?
—May I pick a flower in the garden? — ________.
“必须、不得不” must表示的是说话人的主观看法。 have to 表示的是客观需要。（是由于某种外 界（客观）原因而“必须”，“不得不”做某 事，也可表示经常的或习惯性的事“必须” 做。）
I have to be at my office every evening. 注意： 1.have to的否定形式don’t have to表示不必。 2.have to可用于多种时态中。
1. Mary ____ be in Paris，for I saw her in
the town only a few minutes ago．
A．mustn't
B．can't
C．shouldn't D．may not
2. My MP4 player isn’t in my bag. Where ____ I have put it? A. can B. must C. should D. would
He has to go home now. He had to look after his sick mother.
在情态动词的使用中, 我们要注意以下考点:
1. 情态动词的基本用法。 2 .情态动词表推测的用法。 3. 情态动词+have done 的用法。
can ,could的用法
1.表“能力”
1. In crowded places like airports and railway stations, you___ take care of your luggage. A. can B. may C. must D. will 2. —Must he come to sign this paper himself?
3.表推测，表示主观上的推测，“可能，
也许”，不用于疑问句, might比
may的可能性更小
She may not like this place.
I’m afraid he might not like this place.
Peter ＿＿＿＿ come with us tonight， but he isn’t very sure yet． A．must B．may C．can D．will
2.表“许可”
You may take the boy there He said that I might use his telephone.
— Might I watch TV after supper? — Yes, you ________. A. may B. must C. might D. could