1、Discovering useful structures-Modal Verbs(II)Unit 2Healthy eatingRead the text and find out the sentences containing modal verbs1.Then usually by lunchtime they would all be sold.2.By now his restaurant ought to be full of people.3.What could have happened?4.Nothing could be better 5.Something terri
2、ble must have happened if Li Chang was not coming to eat in his restaurant as he always did.6.He could not believe his eyes.7.Perhaps he should go to the library and find out.8.He could not have Yong Hui getting away with telling people lies!9.Even though her customers might get thin after eating Yo
3、ng Huis food 10.They would become tired very quickly.11.he could win his customers back.Modal Verbs(II)ought(oughtnt)to/should(shouldt)have to/must need/dare can/cantn“应该，要应该，要”，无人称时态和数的变化，无人称时态和数的变化 He ought to come tomorrow.否定式否定式ought not to（oughtnt to）疑问式疑问式Ought sb to?He ought not to be so care
4、less.Ought he to see the doctor?n表推测，按理应该，非常可能表推测，按理应该，非常可能If he started yesterday,he ought to be in Shanghai now.如果他昨天出发的话，现在应该在上海了。如果他昨天出发的话，现在应该在上海了。ought toought(oughtnt)to&should(shouldnt)表责任或者劝告表责任或者劝告“应该应该”，后者语气较强，后者语气较强There is something I ought to tell you before you leave.在你们离开之前我有事要告诉你们。在
5、你们离开之前我有事要告诉你们。You should have a rest after sports.运动之后你应该休息一下。运动之后你应该休息一下。had better 口语中常用，表示最好（做或不做某事）口语中常用，表示最好（做或不做某事）You had better stay here.你最好呆在这里。n“不得不不得不”有人称、时态的变化有人称、时态的变化 Tom has to attend an important meeting this afternoon.今天下午汤姆不得不参加一个重要的会议。今天下午汤姆不得不参加一个重要的会议。have(got)toMust they do?Y
6、es,they must.No,they neednt/dont have to.must have to主观客观主观客观主观主观 客观客观时态时态 现在，将来现在，将来 多种多种表推测表推测询问意愿询问意愿否定意义否定意义mustnt禁止，不允许禁止，不允许dont have to 不必不必(相当相当neednt)nneed“需要需要”和和dare“敢敢”既可用作情态动词，也可既可用作情态动词，也可用作实义动词。用作实义动词。n作情态动词作情态动词主要用于否定句和疑问句。主要用于否定句和疑问句。You neednt telephone him now.She dare not go out
7、alone at night.n作实义动词时，可用于各种句式。作实义动词时，可用于各种句式。You dont need to do it yourself.We need to tell them the news.He did not dare(to)look up.nI dare say为固定习语为固定习语“我想，很可能，大概我想，很可能，大概”I dare say hell come again.大概他将会再来。大概他将会再来。dare&need注意对注意对need问句的回答问句的回答:-Need I finish the work today?-Yes,_.No,_.No,_.you
8、mustyou needntyou dont have toneednt 对其它情态动词的回答对其它情态动词的回答:-Shall I tell John about it?-No,you _.-No,you _.-Must we do it now?-No,you _.-No,you _.needntdont have toneedntdont have tocan&cant(could&couldnt)1.表示能力 2.表示可能He can(not)swim across that river.表可能时,can 常用于疑问句或否定句中-Can the news be true?-No,it
9、cant.表能力表能力“must+have+done”表示对表示对过去过去事情的事情的肯定肯定推测，译成推测，译成“一定做过一定做过某事某事”，该结构，该结构只用于肯定句只用于肯定句。You must have been mad to speak to the servant.你和仆人说话，一定是发疯了。你和仆人说话，一定是发疯了。I didnt hear the phone,I must have been asleep.我没听到电话，我一定是睡着了。我没听到电话，我一定是睡着了。“情态动词情态动词+have done”的用法的用法ncan/could not+have done对对过去过去
10、行为的怀疑或行为的怀疑或不肯定不肯定,表示表示否定推测否定推测。“不可能不可能”Mr.Smith cant have gone to Beijing,for I saw him in the library just now.史密斯先生不可能去北京了，我刚才还在图书馆见过他。史密斯先生不可能去北京了，我刚才还在图书馆见过他。He cant have been to America.他不可能去过美国。他不可能去过美国。n could+have done表示表示“本来可以做而实际上没本来可以做而实际上没做某事做某事”；You could have done better,but you didnt
11、 try your best.你本来可以做得更好，但你没努力。你本来可以做得更好，但你没努力。He could have passed the exam,but he was too careless.本来他能够通过考试，但是他太粗心。本来他能够通过考试，但是他太粗心。nmight/may have done表示对过去发生的动表示对过去发生的动作进行的可能性推测。作进行的可能性推测。“可能已经可能已经”“也许已经也许已经”，He may have gone to the hospital.他可能去医院了。他可能去医院了。nmight的可能性更小。的可能性更小。He might have giv
12、en you more help,even though he was busy.他或许会多给你一些帮助，即使他很忙。他或许会多给你一些帮助，即使他很忙。He might have read about the news in the newspaper.他可能已经从报纸上知道这个消息了。他可能已经从报纸上知道这个消息了。n ought to/should have done 本应该做而实际未做，有本应该做而实际未做，有责备批评的意味。责备批评的意味。意为意为“本应该本应该但但”You should have told her the truth earlier.你应该早点告诉她真相。你应该早
13、点告诉她真相。She shouldnt have left without saying a word.她本不应该一言不发地离开。她本不应该一言不发地离开。You ought not to have told him about the news.你不应该告诉他这个消息。你不应该告诉他这个消息。ought not to/should not have done 本不应该做本不应该做而实际做了而实际做了need have done本需要做某事而实际未做本需要做某事而实际未做neednt have done本不需要做某事而实际上做了本不需要做某事而实际上做了Tom need have cleane
14、d the classroom instead of Lily this morrow.今天早上汤姆本需要代替莉莉打扫教室的。今天早上汤姆本需要代替莉莉打扫教室的。There was plenty of time.I neednt have hurried.(But I hurried.)时间很多，我本不需要着急的。时间很多，我本不需要着急的。You neednt have stayed here.你本不需要留在这。1.You_ all those clothes!We have a washing machine to do that sort of thing.A.neednt have
15、washed B.shouldnt have washedC.must not have washed D.can not have washedA2.Johns score on the test is the highest in the class;he_ last night.A.should study B.should have studiedC.must have studied D.must have to study C3.The room is in a terrible mess;it _cleaned.A.cant have been B.shouldnt have b
16、eenC.mustnt have been D.wouldnt have beenA4.As he had heart attack,he was told that he _ continue the work.A.neednt B.may not C.mustnt D.cant5.Two eyes _see more than one.A.can B.may C.will D.should CA6.You_ to town to see the film yesterday.It will be on TV tonight.A.neednt go B.had better not goC.
17、should not go D.neednt have goneD7.I didnt send out my application form last week,but I _.A.had B.would do C.should have D.might have toC8._ you continue in your efforts and achieve new and greater successes.A.Would B.Will C.May D.Should C 9.You _ your tooth pulled out before it rot completely.A.had better got B.had to get better C.had better to get D.had better getD
