1、情态动词表说话人的某种感情 或语气，对某一动作或状态的 某种态度。表示“需要、可以、 必须、应当”等。,情态动词 ( modal verbs),1) Some of us can use the computer now,but we couldnt last year. 2) The new-built theatre can seat 1500 people.3) Can she be in the computer center? 4) I though what he said could not be true.5) Can/Could I use your dictionary?
2、6) Could you lend me a hand?,1.表能力,3. 表示“请求” “允许”(表请求时，口语中常用could 代替 can 使语气更委婉，回答时用can),2. 表示推测，意为“可能”“或许”，用于疑问句或否定句,1. can 与could,4. 表示“许可”，可与may 换用。,You can go home now.,5. can 用于疑问句或否定句中时，表惊异、 不相信等，意思是“可能、能够”。,How can you say that you really understand the whole Story if you have covered only pa
3、rt of the article?,6. cant/ couldnt +have + done 表示对过去情况的否定推测,Susan cant have written a report like this.,7. could + have + done 表示对过去能做而未做的事情感到惋惜，遗憾,Its a pity. Your class could have got the first prize.,Michael _ be a policeman, for hes much too short.A. neednt B. cant C. should D. may 2. Mr. Bush
4、 is on time for everything. How _ it be that he was late for the opening ceremony?A. can B. should C. may D. must 3. - I stayed at a hotel while in New York.- Oh, did you? You _ with Barbara.A. could have stayed B. could stayC. would stay D. must have stayed My sister met him at the Grand Theater ye
5、sterdayafternoon, so he _ your lecture.A. couldnt have attended B. neednt have attendedC. mustnt have attended D. shouldnt have attended,B,A,A,A,2. may 与might,1. 表示“许可”或“请求”，有“可以”的意思，口语中常用 might 代 may ,表示委婉语气。否定回答时用“must not”表“禁止，阻止”，,Eg: 1)- May I watch TV after supper?- Yes, you may. / No, you mus
6、tnt.,2. 表示可能性。 意为“或许，可能” might 比 may 可能性小。,Eg: 1) It might be true.2) They may be in the library now. 3) Today is Sunday. She may not be in her office now.,3. may/ might as well + 动词原形 “还是的好”,Eg: You may as well go and have a look.,4. May you +动词原形 表“希望、祝愿、祈求” “祝你”,Eg: May you succeed.May you be hap
7、py every day!,1.Sorry Im late. I _ have turned off the alarm clock and gone back to sleep again.A. might B. shouldC. can D. will 2.Peter _ come with us tonight, but he isnt very sure yet. A. must B. mayC. can D. will,A,B,3. will 与would,1. 表“请求、建议”等，用 would 比用will 委婉，客气些,Eg: 1)Will you lend me your b
8、ook?2) Would you like a cup of tea?,2. 用于表示意志或意愿。 will 指现在，而 would 指 过去。,Eg: 1) Ill never do that again.2) They said that they would help us.,3.表示习惯性动作。 译作 “总是、惯于” will 指现在，would 指过去。,Eg: 1)He will often read all night.2) Every evening, she would sit by window, deep in thought.,4. 表示功能，译作“能、行”,Eg: 1
9、) That will be all right.2) This door wont open.,5. 用于否定句中，表示“不肯、不乐意”,Eg: No matter what I say, he wont listen to me.,4. should,1. 用于表劝告、建议。 意为”应该、应当”。,Eg: You should keep your promise.,2. 用于表推测。 意为 “可能、该”,Eg: 1) Its 7 oclock, he should be at home.2) They should have arrived by now.,5. shall 与will,1
10、. Shall 与第一、三人称连用，且用在疑问句中时，表说话人征求听话者的允诺。Will 与第二人称连用，且出现在疑问句中时，表示请求。 Would 更客气。,Eg: 1) Shall I open the window for you?2) Shall the driver wait?3) Will you speak louder, please?,2. shall的主语是第二、三人称的陈述句，表示说话人的允诺、警告、命令等语气。will 的主语是第一、二、三人称的陈述句，表意志、意愿。,Eg: 1)You shall get the book tomorrow.2) He shall b
11、e punished.3) You shall go with me.4) If you will come to my house. I will show you my new painting.,允诺,警告,命令,6. cant,用来表示由于特定事实或环境某事肯定不会发生。,Eg: 1) -Listen, someone is knocking at the door,who can it be?- It cant be Tom, he has gone abroad.2) - Can/ could they have finished the work?- No, they cant
12、have finished the work so soon.,7. must,1. 表示义务或强烈的劝告，意为“必须”“应该”，其否定式表示“不应该”“不许可” “不准”“禁止”。,Eg: 1) You must finish your homework first.2) Children mustnt speak like that to their parents.,2. 回答 must 所在的一般疑问句时，否定回答用“neednt” “dont have to”.,Eg: -Must we finish the work tomorrow?-No, you neednt/ dont h
13、ave to, but you must finish it in three days.,3. 表推测，用于肯定句，意为“一定”“肯定”。,Eg: 1) Betty must be in the next room.2) He must be watering the flowers in his garden.,情态动词 + have done这是历年高考热点之一， 可表示“推测、责备、怀疑” 等多种意义。,一、表示对过去事情的推测或估计,1. The ground is rather wet, so it must have rained last night. must have do
14、ne “想必或肯定已经做了某事” 2. Tom may have gone to shanghai, but I still not sure about it. may/might have done “可能/大概已经做了某事” 3. The ground is very dry, so it cant have rained last night. cant/couldnt have done “不可能已经做了某事” 4. Someone must have broken into our bedroom,Who could have done it? Can/could have don
15、e 疑问句中，对过去的猜测,二、表示对过去所发生事情的遗憾或责备,1. I really regretted wasting the hours when I should have studied hard, but it was too late. should/ought to have done “过去本该做而没做”2. Im very sorry for the words I shouldnt have said to you at that moment. shouldnt/oughtnt to have done “过去不该做的事却做了”3. He could have wor
16、ked out the problem. Could have done “本来能够做的事却没做”,He neednt have come. He didnt need to come.,他本没有必要来（实际也没来）,他本没有必要来（实际却来了）,4. Your home is not far from your school, so youneednt have left in such a hurry. neednt have done “原本不必做的事却做了”,5. I didnt need to clean the windows. My sister did it. didnt need to do/ didnt have to do“ 没有必要做，实际也没做”,6. I would rather have come to help you with yourEnglish, but I was too busy at that time. Would rather have done “本想做却未做成”,
