1、情态动词情态动词modalmodal概述概述情态=情感+态度 表需要、可能、意愿、怀疑等形式：没有人称和数的变化;后加动词原型 加be doing表示动作正在进行，加have done表示动作已经完成。否定其后加not构成 一般疑问句通常将情态动词提到句首review 表示能力 “能，会”You can pass the English exam.I can speak fluent English now,but I couldnt last year.表示请求或许可 “可以”Can I borrow your bike for today?Could we turn the air con
2、ditioner on?表示猜测“可能”As a human being,anyone can make a mistake.You couldnt have seen me there.表意愿,决心等 I wont do anything against her.He would finish the task the boss ordered him to do.表经常性，习惯性，倾向性，I will finish my work at the first ime.He would have coffee with his college before he retired.表功能，性质
3、The tree will live without water for 3 months.表估计:想必，大概(只时态区别)That will be the messenger ringing.The person you mentioned would be her father 表请求/要求Will you please take a message for him?Would you please tell me your telephone number?shall 表征求意见(好不好)Shall we go camping this weekend.表允诺、威胁、警告、命令Dont
4、worry,you shall get the answer this afternoon.表规章、法令、预言:必须Passengers shall not talk with the driver while the bus is moving.Should 责任，义务或要求 You should pay more attention to what your teacher says.推测和可能性，是(按理说)应该”He should be around sixty years old.If things should change suddenly,please let me know.
5、用于疑问句或感叹句中，表示意外、惊异，意为“竟会”Dont ask me.How should I know?表示必须、必要 （neednt）You must go back home with him early this evening.表示推测，意为“准是”“一定是”They must have finished their meal.The mother is washing dishes.表示非要，偏要Must you open the window?Its so cold outside.mustnt意思为不许、不准，表示禁止。You mustnt play football in
6、 the street.There is nothing I need fear.He doesnt need to wear glasses all the time.Does anybody need to see the doctor?You neednt have come last night.应该表义务、责任或劝告 Such things ought not to be permitted.We oughtnt to take risk.I dont think you ought to have done that.推断，意思为“应该”、”可能“I ought to go abr
7、oad for further study next month.You oughtnt to be talking so much under this situation.You ought to be hearing from me soon.He would rather get advice from his parents.Id would rather play volleyball than do kungfu.Id rather you didnt talk about this to anyone.Our parents would never do anything to
8、 hurt us.Would you rather choose the old one?study Dare作情态动词时，敢于,主要用于疑问句、否定句和条件从句中，一般不用在肯定句中。Dare you tell her the truth?Yes,I dare./No,I darent.How dare you accuse me of lying!He darent admit this.Dare作实义动词时，在肯定句中，dare后接带to的不定式Only a few journalists dared to cover the story.He doesnt dare(to)go the
9、re alone.Dont you dare(to)touch it?How_ you accuse me of cheating in the exam!He_ admit that he spending all his money in gambling.If you _ do such a thing,you are sure to be punished.If he_ say such a thing again,I shall knock him down.daredarentdaredare 作情态动词时，需要、必须,主要用于疑问句、否定句You need not admit t
10、he entire truth.Need I do my homework now?-Yes,you must.-No,you neednt/dont have to.作实义动词时，后接带to的不定式I need to know the truth.He needs to practice more.Your car needs washing=Your car needs to be washed.You neednt have told him this news.He knew it already.归纳拓展：lsb needs sth表示”某人需要某物”lsb needs to do
11、sth，表示”某人需要去做某事”lsth need doing.某事需要被做=need to be donelneed/neednt+动词完成式，表示过去”需要但实际未做“或”过去不需要，但却做了I didnt _ to buy the dictionary.I had a copy at home.The team _ to finish their project before this year.You neednt _(take)it seriously yesterday.They needed _(help)others with the difficulty.needneedsh
12、ave takento helpYou dont have to tell him about the sad news.He was able to flee Europe before the war broke out.They will be able to tell you the news soon.Are you able to finish the task this morning?Lingling has been able to play the piano for over 2 years.The fire was very big,but most people we
13、re able to escape from the building.The young man has to work for 16 hours a day to earn enough money.He doesnt have to do the homework now.He had to look after his sister last week.We didnt have to answer the question yesterday.Do I have to go there now?Yes,you do.No,you dont have to.have to则往往强调客观
14、需要,而must表示的是说话人的主观看法。I had to work when I was your age.The play is not interesting.I really must go now.have有更多的时态形式,must一般只表现在一般现在时。二者的否定意义不大相同。You dont have to go.你不必去。You mustnt go.你可不要去。had better 只有一种形式，它后面要跟动词原形。had better do sth had better not do sthIt is pretty cold outside.Youd better put o
15、n your coat.He just left,you had better have come earlier.You had better not smoke for there are some babies.Hadnt we better stop now?1.Nothing is hard in the world,if you _scale the heights.2.You_ have watered the plants,for it is going to rain.3.He _ speak English before such a crowd,dare he?4.Do
16、they _ pay their bill before the end of the month?5.Ive always wanted to _speak fluent English.dareneedntdarenthave to be able to 6.He _ go because of somebodys calling him that day.7.In order to take the exam,we_ finish the whole book by the end of this month.8.Its dark already,we _ go back homewor
17、k.9.My brother was very ill,so I _ call the doctor in the middle of the night.10.Those bags look really heavy,are you sure you_ to carry them on your own?had towill have tohad betterhad towill be able11.You _ sit here and have a rest before having next try.12.I _ leave school because my family is po
18、or now.13.I wonder if we _ take sleeping bag.14.If he _ say such a thing again,I shall knock him down.15.After the accident it was a long time before she _ walk again.had better have toneeddare was able to口诀:情态动词两特点动词原形接后面，说话语气较委婉。can 能力may许可，must责任或义务。否定回答neednt换，需要need,dare敢。should应该，would愿，have to被迫表客观。thank youthank you
