人教版高中英语必修三情态动词基本用法

ought to 和should
• 1) ought to ： 比should语气强烈,一般用于肯 定和否定句 • They ought to be there by now. • You ought not to be late again. • ought to have done sth. =should have done sth. 本应该做某事而没有. • ought not to have done sth.=should not have done sth. 本不应该做某事而做了. • They ought to have handed in the paper yesterday. 他们本应当昨天交论文。 • You ought not to have wasted your time.
(3)用于疑问句或表示提议的句子，请 求听者决定之． 1)---Shall we go together? ---Yes, let’s. 2)---Shall I get you a chair? ---Yes, please. 3)---Shall the visitor come in now? ---I’d rather he came in later.
WBiblioteka Baiduat are 情态动词(modal verbs)?
情态动词的特点 • 情态动词有一定的意义 • 无人称和数的变化 • 通常不带to ,后接动词原形 • 表示说话人的语气或情绪
情态动词备考方向:
• • • • 1. 各情态动词的基本用法; 2. 易混淆情态动词的辨析; 3.情态动词在特定语境中的用法 4.虚拟语气中情态动词的用法.
2. may/might
• • • • • • • • • • 1)表示请求\许可 ---May/Might I come in? ---Yes, you may. 2)表示可能性的推测 Her appearance has changed so much that you may well not recognize her. It‟s so late. I thing he may/might have gone to bed. You might have given him more help, but why didn‟t you? 3) may用于祈使句表示祝愿 May you succeed! May you return in safe!
判断正误: How dare you say such a thing? How dare you to say such a thing?
He daren’t to speak English before such a crowd, did he? He daren’t speak English before such a crowd, dare he?
7. dare I daren’t ask her for a rise. How did you dare to tell her that? I wonder whether he dare stand up in public. I don’t know how she dares to wear that dress.
(6). 用于so that 和in order that 之后表示目 的或动机． He put the cases in the car so that he should be able to make an early start. He repeated the instructions slowly in order that he should understand. (7)用于表示请求的客气说法． I should like to make a phone call, if possible. We should be grateful for your help.
Should 的用法
(4).用于形容词anxious, sorry, concerned, happy, delighted 等后接的从句中． We are sorry that you should feel uncomfortable. That he should speak to you like that is quite astonishing. (5).用于if 和in case引导的从句表示某事不太可 能． If you should change your mind, do let me know. Should anyone telephone, please tell them I‟m busy.
• (8).用于表达不成熟的意见． I should say she‟s over forty. I should imagine It will take about three hours. (9). 与疑问词连用表示不感兴趣，难以置信等 How should I know? Why should he think that? I turned round on the bus and who should be sitting behind me but my ex-wife.
How many modal verbs can you remember?
will/would
can/could
have/had to used to ought to
dare
may/might
modal verbs
shall/should must
need
1. can/could
• • • • 1)表示能力 He can play table tennis quite well. 2) 表示事物一时的特征, 理论上的可能性 It‟s always warm here, but sometimes it can be very cold. • He‟s good-tempered. However, he can be hard to deal with when offended. • Even an experienced teacher can make mistakes.
3. must
• • • • • • • • • • • • 1. 必须 Must I say “sorry”? Yes, you must. / No, you needn‟t. You must see a doctor. 2. 猜测 “肯定,准是” She must be watching TV now. There must be some mistake. It must have rained last night. The ground is so wet. 3. “偏要,硬要” If you must smoke, please go out. 4. 否定,表示 “禁止” You mustn‟t play with fire. You may hurt yourself.
7.可兼做行为动词的情态动词：need 、 dare 情态动词 (+动词原形) 行为动词
1.无人称和数的变化; 多用于肯定句; need 2.尤其用于： (sb.) need to do *否定句及疑问句中; dare to do *在if/whether之后; . (sth.) need to be *或与hardly, never, no one, nobody连用; done dare 3.常以needn’t 和daren’t (sth.) need doing 的形式出现; 4.dare有其过去时dared.
• • • •
3)表示许可/允诺 ---Can/Could Tom use the car? ---Yes , he can. You can have my seat. I am going now.
• 4) 表示推测 • 1) ---Someone is knocking at the door. Who can it be? Can it be Scarlet? • ---No, it can‟t be her. She called from Tokyo just now. • 2) He can not have forgotten it. • 3) The accident could have been avoided.
7. need Do you need any help? I wonder whether he need send it immediately. I need hardly tell you that the work is dangerous. The garden doesn’t need watering at the moment. You needn’t finish that work today.
4.Shall的用法
(1). Shall 常用于第一人称表示简单的将来 When shall well meet again? I shall have finished my homework by Friday. (2) shall用于第二，三人称表示： a. 允诺或强烈的意志 It shall be done as you wish. You shall get a bike as your birthday present. B. 肯定会发生的事情 That day shall come. C.命令或必须执行之事． This law shall have effect in Scotland.
5.Should 的用法
• （１） 用于表示义务或责任 You shouldn‟t drink and drive. Visitors should inform the receptionist of their arrival. (2)用于表示劝告或推荐 He should stop smoking. You shouldn‟t leave the baby alone in the house. They should have called the police. (3)用于表示假定的结果 If I was asked to work on Sundays , I should resign. We should move to a larger house if we had the money.
• 做助动词 :表示单纯的将来)将 He will be home at six. 他六点回家。 • 做情态动词: • 1) (表示意志、意愿)愿,要 You will come, won't you? 你会来的,是不是? • 2) (表示经常性、习惯性)经常,惯于,总是 These things will happen. 这种事总是要发生的。
must对比have to
• 1) 两词都是‘必须’的意思，have to 表示客观的需 要， must 表示说话人主观上的看法，既主观上的必 要。 • My brother was very ill, so I had to call the doctor in the middle of the night. • He said that they must work hard. • 2) have to有人称、数、时态的变化，而must只有一 种形式。 • He had to look after his sister yesterday. • 3） 在否定结构中： don„t have to 表示“不必” mustn‟t 表示“禁止” • You don„t have to tell him about it.
8. used to do sth 过去常常做某事
• I used to go to the cinema a lot. • He used to be a heavy smoker, didn‟t he? • He used to be a heavy smoker, usedn‟t he?
9. will