高中情态动词用法总结
高中英语知识点归纳语法情态动词的运用
高中英语知识点归纳语法情态动词的运用高中英语知识点归纳：语法情态动词的运用高中英语中，语法知识点千变万化，其中一个重要的部分就是情态动词的运用。
掌握了情态动词的用法，可以帮助我们更准确地表达自己的意思，提升英语写作和口语表达能力。
本文将对高中英语中常见的情态动词进行归纳总结，并分别从推测、建议、允许、请求和义务五个方面进行讲解。
一、推测(speculation)1. must"must"表示推测时，常用于对现在情况进行推理，表示事物发生的可能性很大。
例如：He must be at home. (他肯定在家。
)2. might"might"是"may"的过去时态形式，表示推测时，表示事物发生的可能性较小。
例如：He might be at home. (他可能在家。
)3. could"could"表示推测时，表示事物发生的可能性较小。
例如：He could be at home. (他可能在家。
)4. can't"can't"表示推测时，表示肯定事物不可能发生。
例如：He can't be at home. (他不可能在家。
)二、建议(suggestions)1. should"should"常用于表示建议，用于表达应该或者应当发生的事情。
例如：You should go to bed early. (你应该早点睡觉。
)2. could"could"也可用于表示建议，表示某事情是可能发生的。
例如：You could try to study harder. (你可以努力学习。
)三、允许(permissions)1. can"can"表达某事物有权利、能力或许可做某事。
例如：You can go out to play. (你可以出去玩。
情态动词高中知识点高三
情态动词高中知识点高三情态动词是一类具有特殊意义和用法的动词，它们在句子中一般与实义动词连用，表示说话人的推测、命令、请求、建议等情态。
在高中英语学习中，掌握情态动词的正确用法至关重要。
本文将介绍情态动词的相关知识点，帮助高三学生更好地运用这一语法现象。
一、情态动词的定义情态动词，又称情态助动词，是用来表示说话人对某种动作或状态的态度、推测、可能性、能力、意愿、义务等情态的一类特殊动词。
常见的情态动词包括can、could、may、might、must、shall、should、will、would等。
二、情态动词的用法1. 表示能力情态动词can表示某人具有能力或可能做某事，could用于过去说法。
例如：- She can speak three languages fluently.（她能说流利的三种语言）- He could lift the heavy boxes when he was younger.（他年轻时能搬起这些沉重的箱子）2. 表示推测和可能性情态动词may、might、could用于表示推测和可能性。
may用于表示较为肯定的推测，might和could表示推测的可能性较小。
例如：- The weather is cloudy, it may rain later.（天气多云，可能会下雨）- He might be late for the meeting.（他可能会迟到会议）3. 表示义务和建议情态动词must表示说话人对某种行为具有强烈的责任感或坚决要求，should表示建议。
例如：- We must obey the laws of the country.（我们必须遵守国家的法律）- You should apologize to your friend for your mistake.（你应该为你的错误向朋友道歉）4. 表示许可和请求情态动词can、may、could用于表示允许和请求。
高中英语语法——情态动词总结(附带练习)
情态动词总结I 情态动词的特征：1.本身有词义。
2.不能独立作谓语。
2. 后接动词原形一起构成谓语。
3. 不随人称和数的变化。
II 情态动词各自的基本意义及用法：1.大多数情态动词（除表‘能力、许可、意志’外），都可以表示推测，其程度有差异。
按可能性程度的高低排列为：must﹥will ﹥would ﹥ought to ﹥should完全肯定完全可能很可能﹥can ﹥could﹥may ﹥might可能有可能2. 区分情态动词的否定含义：may not或许不、可能不might not可能不can’t 不可能mustn’t不许、禁止shouldn’t不应该needn’t 不必1.情态动词表推测的反意疑问句，简单来说，就是以情态动词后的时态为淮，如句子里有明确的时间状语，则以其为准。
2.以must 为例：E.g. 1. You must be hungry now, aren’t you?2. He must be watching TV , isn’t he ?3 Tom must have lived her for a long time, hasn’t he ?4. She must have arrived yesterday, didn’t she?注：如选择题中（以She must have arrived yesterday, didn’t she？为例）既有didn’t she又有hasn’t she则以didn’t she？为最佳答案。
IV 情态动词专项练习与解析一( ) 1. You _____ return the book now. You can keep it till next week if you like.A. can’tB. mustn’tC. needn’tD. may not( ) 2. Where is my pen? I _____ it.A. might loseB. would have lostC. should have lostD. must have lost( ) 3. I wish I _____ you yesterday.A. seenB. did seeC. had seenD. were to see( ) 4. I didn’t hear the phone. I _____ asleep.A. must beB. must have beenC. should beD. should have been( ) 5. If my lawyer _____ here last Saturday, he _____ me from going.A. had been; would have preventedB. had been; would preventC. were; would preventD. were; would have prevented( ) 6. He _____ you more help, even though he was very busy.A. might have givenB. might haveC. may have givenD. may give( ) 7. If it _____ for the snow, we _____ the mountain yesterday.A. were not; could have climbedB. were not; could climbC. had not been; could have climbedD. had not been; could climb( ) 8. Without electricity human life _____ quite difficult today.A. isB. will beC. would have beenD. would be( ) 9. A computer _____ think for itself, it must be told what to do.A. can’tB. couldn’tC. may notD. might not( ) 10. Jenny _____ have kept her word. I wonder why she changed her mind.A. mustB. shouldC. needD. would( )11. We _____ last night, but we went to the concert instead.A. must have studiedB. might studyC. should have studiedD. would study( ) 12. — Could I borrow your dictionary?— Yes, of course you _____.A. mightB. willC. canD. should( ) 13. Tom ought not to _____ me your secret, but he meant no harm.A. have toldB. tellC. be tellingD. having told ( ) 14. — If he _____, he _____ that food.— Luckily he was sent to the hospital immediately.A. was warned; would not takeB. had been warned; would not have takenC. would be warned; had not takenD. would have been warned; had not taken ( ) 15. Peter _____ come with us tonig ht, but he isn’t very sure yet.A. mustB. mayC. canD. will( ) 16. I told Sally how to get here, but perhaps I _____ for her.A. had to write it outB. must have written it outC. should have written it outD. ought to write it out( ) 17. I didn’t see your sister at the meeting. If she _____, she would have met my brother.A. has comeB. did comeC. cameD. had come ( ) 18. — Shall I tell John about it?—No, you _____. I’ve told him already.A. needn’tB. wouldn’tC. mustn’tD. shouldn’t ( ) 19. When a pencil is partly in a glass of water, it looks as if it _____.A. breaksB. has brokenC. were brokenD. had been broken( ) 20. It’s nearly seven o’clock. Jack _____ be here at any moment.A. mustB. needC. shouldD. can( ) 21.— There were already five people in the car but they managed to take me as well.— It _____ a comfortable journey.A. can’t beB. shouldn’t beC. mustn’t have beenD. couldn’t have been ( ) 22. Johnny, you _____ play with the knife, you _____ hurt yourself.A. won’t; can’tB. mustn’t; mayC. shouldn’t; mustD. can’t; shouldn’t ( ) 23. The fire spread through the hotel very quickly but everyone _____ get out.A. had toB. wouldC. couldD. was able to ( ) 24. — When can I come for the photos? I need them tomorrow afternoon.— They _____ be ready by 12:00.A. canB. shouldC. mightD. need( ) 25. — I stayed at a hotel while in New York.— Oh, did you? You _____ with Barbara.A. could have stayedB. could stayC. would stayD. must have stayed ( ) 26. — Will you stay for lunch?— Sorry, _____. My brother is coming to see me.A. I mustn’tB. I can’tC. I needn’tD. I won’t( ) 27. — Are you coming to Jeff’s party?—I’m not sure. I _____ go to the concert instead.A. mustB. wouldC. shouldD. might( ) 28. — Write to me when you get home.— _____.A. I mustB. I shouldC. I willD. I can( ) 29. I was really anxious about you, you _____ home without a word.A. mustn’t leaveB. shouldn’t have leftC. couldn’t have leftD. needn’t leave( ) 30. — Is John coming by train?— He should, but he _____ not. He likes driving his car.A. mustB. canC. needD. may专项练习（二）1. I didn’t see her in the meeting room this morning. She _____ at the meeting.A. mustn’t have spokenB. shouldn’t have spokenC. needn’t have spokenD. couldn’t have spoken2. One ought _____ for what one hasn’t done.A. not to be punishedB. to not be punishedC. to not punishedD. not be punished3. If you really want yourself to be in good health, you must ___ always ___ so much.A. not; be smokingB. not; have smokedC. not; to smokeD. be not; smoking4. With so much work on hand, you _____ to see the game last night.A. mustn’t goB. shouldn’t goC. couldn’t have goneD. shouldn’t have gone5. Most of the students felt rather disappointed at the English party. They say that it ______ better organized.A. had beenB. had to beC. must have beenD. could have been6. I’m surprised that he _____ in the exam.A. should failB. would have failedC. may have failedD. should have failed7. The little girl _____ there alone.A. not dare goB. dares not goC. dare not goD. dare not to go8. “Must we do it now?” “No, you _____.”A. won’tB. needn’tC. can’tD. don’t9. He said he would rather not _____ it right now.A. doingB. to doC. doD. to be doing10. You _____ to the meeting this afternoon if you have something important to do.A. needn’t to comeB. don’t need comeC. don’t need comingD. needn’t come11. Put on more clothes. You _____ be feeling cold with only a shirt on.A. canB. couldC. wouldD. must12. I _____ play football than baseball.A. would ratherB. had betterC. like betterD. prefer13. I thought you _____ like something to read, so I have brought you some books.A. mayB. mightC. couldD. must14. There was plenty of times. She _____.A. mustn’t have hurriedB. couldn’t have hurriedC. must not hurryD. needn’t have hurried15. The plant is dead. I _____ it more water.A. will giveB. would have givenC. must giveD. should have given16. You _____ return the book now. You can keep it till next week if you like.A. can’tB. mustn’tC. needn’tD. may not17. It’s still early, you _____.A. mustn’t hurryB. wouldn’t hurryC. may not hurryD. don’t have to hurry18. Please open the window, _____?A. can’t youB. aren’t youC. do youD. will you19. We _____ for her because she never came.A. mustn’t have waitedB. shouldn’t have waitedC. mustn’t waitD. needn’t wait20. — May I stop here? — No, you _____.A. mustn’tB. might notC. needn’tD. won’t21. It’s a fine day. Let’s go fishing, _____.A. won’t weB. will weC. don’t weD. shall we22. I didn’t see her in the meeting room this morning. She _____ at the meeting.A. mustn’t have spokenB. shouldn’t have spokenC. needn’t have spokenD. couldn’t have spoken23. — Please don’t make a noise. — _____. I’ll be as quiet as a mouse.A. Yes, I won’tB. No, I won’tC. No, I willD. Yes, I will24. The young man has made so much noise that he _____ not have been allowed to attend the concert.A. couldB. mustC. wouldD. should25. — Where is John? — He _____ in the library.A. should beB. must beC. can beD. must have been26. Since the road is wet this morning, _____ last night.A. it must rainB. it must be rainingC. it must have rainedD. it must have been rain27. — Will your brother stay home tonight?— I’m not quite sure. He _____ to the cinema tonight.A. must goB. can goC. may goD. may be going28. She’s already two hours late. What ______ to her?A. can have happenedB. may have happenedC. should have happenedD. must happen29. You must be a writer, _____?A. mustn’t youB. are youC. must youD. aren’t you30. I got up early that morning, but I _____ so because I had no work to do.A. mustn’t have doneB. didn’t need to doC. needn’t have doneD. can’t have done31. He _____ have come here yesterday, but he didn’t.A. couldB. shouldC. ought toD. all the above32. I missed the last bus, so I _____ go home on foot.A. mustB. have toC. mayD. had to33. He ought to win the first prize, _____ he?A. oughtn’tB. shouldn’tC. mustn’tD. both A and B34. Everyone _____ do his best for the modernizations of our country.A. canB. mayC. shouldD. might35. Let’s clean our classroom, _____?A. will youB. don’t weC. shall weD. do you36. Let us play basketball, ______?A. will youB. don’t weC. shall weD. do you37. He asked me for this book many times. Please tell him that he _____ have it tomorrow.A. mustB. mayC. shallD. both B and C38. “Your phone number again? I _____ quite catch it.” “It’s 9568442.”A. didn’tB. couldn’tC. don’tD. can’t39. Mother _____ us stories when we were children.A. was used to tellB. is used to tellingC. used to tellD. used to telling40. She would rather _____ more money on books _____ on clothes.A. cos t … notB. to spare … don’tC. pay … thanD. spend … than专项练习（三）1. — Has Li Lin started? He said he would join in the party.— He ______. He is a man of keeping his word.A. could have leftB. must have leftC. can’t comeD. won’t be c oming2. — May I park my car here?— No, you ______. No car is allowed to park here.A. may notB. needn’tC. mustn’tD. daren’t3. — Excuse me, could you tell me where the Yajia Supermarket is?—It’s two blocks straight ahead. You ______ miss it.A. mustn’tB. can’tC. needn’tD. shouldn’t4. — I saw Mr. Sun at Tongyu Station this morning.—You ______. He’s still on holiday in Hawaii.A. couldn’t haveB. mustn’t haveC. shouldn’tD. needn’t5. — How about paying a visit to Dr. Wang, our former Chinese teacher?— Good idea. I will e-mail him today so that he ______ know ______ to expect us.A. shall; whyB. could; whenC. would; whatD. will; how6. Everything has two sides. Beautiful songs, sometimes, ______ be just noise to others.A. mustB. mayC. shouldD. could7. Someone ______ my umbrella. I found it wet yesterday.A. must be usingB. must have usedC. must useD. must have been using8. — How dangerous it was!— Yes, but for the passer-by’s quick action, th e girl ______.A. was drownedB. could have been drownedC. had drownedD. should be drowned9. You ______ scold such a pupil who always keeps silent so seriously that you ______ hurt him.A. should; canB. may; willC. mustn’t; mayD. can’t; must10. — Why does Alice know so much about Angkor Wat?— She ______ have been there, or ...A. mustB. oughtn’t toC. mayD. can’t11. —You may laugh, but I’ve been thinking of becoming a vegetarian.— Oh, you ______ be crazy. You will be hungry all the time.A. mustB. mayC. willD. need12. —What’s the matter with you?—Oh, I’m not feeling well in the stomach. I ______ so much fried fish just now.A. shouldn’t eatB. mustn’t have eatenC. shouldn’t have eatenD. mus tn’t eat13. — ______ he have been chosen as captain of the football team?— Yes, he ______.A. Can; must haveB. Must; must haveC. Can; mustD. Must; must14. Mr. Zhang ______ in Shanghai tomorrow morning.A. can have arrivedB. will have arrivedC. may have arrivedD. must have arrived15. Miss Wang started at 8 o’clock, and she ______ be there now.A. shouldB. canC. can’tD. need16. — It must be Mr. Li who did it. — No, it ______ be Mr. Li.A. mustn’tB. wouldn’tC. can’tD. may17. You ______ finish reading the book as soon as possible.A. mayB. canC. needD. should18. — Need you go to work now? — Yes, I ______.A. mustB. needC. canD. dare19. Your trousers are dirty. ______ them for you?A. Shall I washB. Will I washC. Am I going to washD. Am I washing情态动词专项练习与解析一【练习解析】1．C 从原题中You can keep it till next week if you like这一信息句可知，“你不必现在还”。
高中英语知识点归纳情态动词的复合用法与考点
高中英语知识点归纳情态动词的复合用法与考点高中英语知识点归纳：情态动词的复合用法与考点情态动词是英语中常见的一类词汇，具有特殊的语法和用法。
它们在句子中常常与其他动词搭配使用，用于表示各种语气、态度和推测等。
本文将归纳总结高中英语中情态动词的复合用法，并分析其中的考点。
一、can/could1. 表示能力和技能：e.g. She can swim very well.e.g. I could speak three languages when I was younger.2. 表示请求和允许：e.g. Can I borrow your pen, please?e.g. Could you open the door for me?3. 用于提出建议和给出意见：e.g. You can try contacting him tomorrow.e.g. I could suggest a few books for you to read.4. 表示可能性和推测：e.g. It can be a difficult task.e.g. He couldn't have arrived here so early.二、may/might1. 表示允许和请求：e.g. May I use your phone?e.g. Might I have a glass of water, please?2. 表示可能性和推测：e.g. It may rain later.e.g. He might be running late for the meeting.3. 用于表达祝愿和提出建议：e.g. May you have a wonderful journey.e.g. You might want to consider studying abroad.三、must1. 表示强烈的责任和义务：e.g. I must finish my homework before going out.e.g. We must obey the rules and regulations.2. 表示肯定的推断和确定：e.g. He must be the new teacher.e.g. They must have left already.四、shall/should1. 表示将来的计划和意图：e.g. We shall meet at the library tomorrow.e.g. I should go to bed early tonight.2. 表示义务和建议：e.g. You shall obey the rules of the school.e.g. We should do our best to protect the environment.五、will/would1. 表示未来的动作和事件：e.g. He will come to the party tomorrow.e.g. We would like to invite you to our wedding.2. 表示习惯和倾向：e.g. She will always help others in need.e.g. He would often go for a walk in the park.3. 用于提出请求和邀请：e.g. Will you please pass me the salt?e.g. Would you like to join us for dinner?六、ought to1. 表示应该和责任：e.g. You ought to apologize for your behavior.e.g. They ought to take care of their health.2. 用于提出建议和表示期望：e.g. You ought to study harder for the exam.e.g. They ought to arrive on time for the meeting.在高中英语考试中，情态动词的复合用法常常成为考点。
高中英语知识点归纳情态动词的用法与推测技巧
高中英语知识点归纳情态动词的用法与推测技巧高中英语知识点归纳：情态动词的用法与推测技巧在英语学习中，情态动词是一个重要的语法知识点。
情态动词包括can, could, may, might, shall, should, will, would, must, need, ought to等。
它们在句子中具有特殊的功能和用法。
本文将为大家介绍情态动词的用法和推测技巧。
一、情态动词的用法1. 表示能力和可能性Can和could常用于表示能力和可能性。
例如：- I can swim.（我会游泳。
）- He could run very fast when he was young.（他年轻时可以跑得很快。
）- It can be difficult to learn a new language.（学习一门新语言可能很困难。
）2. 表示请求、许可和建议情态动词can, could, may, might和will常常用于表示请求、许可和建议。
例如：- Can you help me with my homework?（你能帮我做作业吗？）- Could I borrow your pen?（我能借用你的钢笔吗？）- May I ask a question?（我可以提问吗？）- You should go to bed early.（你应该早点睡觉。
）3. 表示推测和可能性情态动词may, might, could和must用于表示推测和可能性。
例如：- He may be at home.（他可能在家。
）- She might pass the exam.（她也许会通过考试。
）- It could rain tomorrow.（明天有可能下雨。
）- He must be tired after running for so long.（他跑了这么久肯定累了。
）4. 表示义务和建议情态动词must和should常常用于表示义务和建议。
高中英语语法：情态动词的详解大总结
高中英语语法：情态动词的详解大总结一、can和could1、can的用法（1）表示体力和脑力方面的能力。
（2）表示对现在的动作或状态进行主观的猜测，主要用在否定句和疑问句中。
（3）表示可能性，理论上的可能性，意为“有时候可能会”，可用于肯定句。
（4）表示允许，意思与may接近。
（5）表示说话人的推测、怀疑、惊异、猜测或不肯定等，主要用于否定句、疑问句或感叹句中。
（6）can的特殊句型cannot…too / enough表示“无论怎么...也不过分”“越...越好”cannot but+ do sth.表示“不得不，只好”2、could的用法（1）表示能力，指的是过去时间。
（2）表示允许，指的是过去时间。
（3）表示可能，可以指过去时间，也可以指现在时间，表示语气缓和。
（4）委婉客气地提出问题或陈述看法，指的是现在时间。
主要用于疑问句，回答时用can。
3、can与could的区别can表推测时只用于否定句和疑问句（could无此限制）。
couldn’t的可能性比can’t小。
4、can与be able to的区别（1）现在时：无区别，但后者不常用。
（2）完成时;can没有完成时，此时要用have （has,had）been able to。
（3）将来时：can没有将来时，要用will be able to。
（4）过去时：could表示一般能力，was/were able to 表示在具体场合通过努力成功做成某事的能力。
二、may 和might1、may的用法（1）表示询问或说明一件事可不可以做。
（2）表示一件事或许会发生或某种情况可能会存在，通常用在肯定句和否定句中。
注意：表示可能性时，can’t语气强，表示“不可能”，may not语气弱，表示“可能不”。
2、might的用法（1）表示询问或允许，指的是过去时间。
（2）表示可能发生的事，可以指过去时间，也可以指现在时间，语气更加不肯定，可能性比may小一些。
高中英语语法之情态动词
高中英语语法之情态动词一、概念情态动词是表示能力,义务,必须,猜测等说话人的语气或情态的动词。
二、相关知识点精讲1．can1)表能力can 表能力时意味着凭体力或脑力或技术等可以无甚阻力地去做某事。
I can climb this pole.我能爬这根杆子。
He is only four , but he can read.他只有4岁，但已认得字了。
Fir e can’t destroy gold.火烧不毁金子。
因为 can 不能和其他助动词连用，所以表示将来式时用will be able to。
You will be able to skate after you have practiced it two or three times.你练习两三次后就会溜冰了。
2)表可能性多用于否定与疑问结构中，但也可用在肯定句中。
Can the news be true?这消息可能是真的吗？It can’t be true.它不可能是真的。
What can he possibly mean?他可能是什么意思？can 用在肯定句中表示理论上的可能性（一时的可能）。
Attending the ball can be very exciting.The road can be blocked.这条路可能会不通的。
may 在肯定句中表示现实的可能性。
The road may be blocked.这条路可能不通了。
3)表示允许（和 may 意思相近）常见于口语。
Can (May) I come in ?我能进来吗？Can I smoke here ?我可以在这里抽烟吗？2.could 的用法1)表过去的可能和许可，（多用于间接引语中）At that time we thought the story could not be true.那时我们认为所说的事不可能是真的。
Father said I could swim in the river.爸爸说我可以在河里游泳。
高中情态动词用法
情态动词1、could/might/would/should表委婉语气的功能。
如：－Could/Might I use your bike tomorrow morning?－Yes, you can/may。
（否定：No, I’m afraid not / you mustn’t）2、回答用need提单的问句时与回答must提问的问句时一样，肯定回答用must(口语中也可以用have to 或 have got to )，否定回答要用needn’t 或don’t have toNeedI do it at once?－Yes, you must./ No, you needn’t (或don’t have to )Must3、shall的用法要点(1) 用于第一、第三人称疑问句中，表示说话人征求对方的意见和向对方请示。
Shall we begin our class? Shall the driver wait outside?(2) 用于第二、第三人称陈述句中，表示说话人给对方的命令、警告、允诺或威胁。
You shall go with we.（命令） He shall be punished.（威胁）You shall have the book when I finish it.（允诺）★(3) 当宣布法律、规定时也要用shall。
如：It has been announced that candidates shall remain in their seats until all the papers have been collected. 在所有试卷收上来之前，应试者必须留在座位那里。
（规则或规定）二、表能力can表现在的能力be able towill be able to：表将来的能力could表过去的能力was/were able to如：I am starving to death. I can eat two bowls of rice now.（现在的能力）If you have a good sleep, you will able to work out this problem. (将来的能力)The fire spread through the hotel very quickly but everyone was able to get out. (克服困难而成功做某事的能力)三、表推测（可能性）1、表示具体事情实际发生的可能性的层次比较（见下表）E.g. －Are you coming to Jeff’s party?－I’m not sure. I might go to the concert instea d.（表示不确定）四、情态动词其它用法要点1、need和dare的用法need和dare两者既可以用作情态动词也可用作作为动词。
高中英语知识点归纳情态动词的用法和辨析
高中英语知识点归纳情态动词的用法和辨析情态动词是英语中的一类特殊动词，它们用来表示说话者对某种行为、能力、必要性等方面的态度或推测。
情态动词包括can, could, may, might, must, shall, should, will, would等。
它们在句子中有一定的用法和辨析。
一、can与could1. 表示能力与可能can用于一般现在时和一般未来时，表示肯定的能力或可能性；e.g. He can swim.（他会游泳。
）I can solve this problem.（我能解决这个问题。
）could则用于过去时，表示过去某一时间的能力或可能性。
e.g. When I was young, I could run very fast.（当我年轻的时候，我跑得很快。
）2. 请求与许可can用于一般现在时，表示请求或征询许可；e.g. Can I borrow your pen?（我可以借用你的笔吗？）Could则更加委婉，用于礼貌地请求或征询许可。
e.g. Could you please help me with the homework?（你能帮我做作业吗？）二、may与mightmay用于一般现在时和一般未来时，表示较正式的许可或征求对方意见。
e.g. May I use your phone?（我可以用你的电话吗？）might则表示过去或将来的一种可能性，常用于虚拟语气中。
e.g. If it rains tomorrow, we might stay at home.（如果明天下雨，我们可能会呆在家里。
）三、must1. 表示推测或推理must用于一般现在时和一般过去时，表示根据已有的客观事实或推理得出的合理推测。
e.g. He has been studying hard, so he must pass the exam.（他一直在努力学习，所以他一定会通过考试。
）2. 表示义务或必要性must用于一般现在时和一般过去时，表示说话者的主观认识或认为事物具有必然性或必要性。
高中情态动词总结
情态动词主要有can, may, must, could, might, shall , should, will, would, ought to, need, dare等。
情态动词与其他动词连用表示说话人的语气。
情态动词可表达建议、要求、可能和意愿等。
情态动词没有人称和数的变化。
情态动词+动词完成式情态动词+动词完成式即“情态动词+ have + done分词”，表示对过去行为或动作进行推测、评论或判断。
1. must have donemust have done 表示对过去某事的肯定猜测。
其否定或疑问形式都用can(could) 来表示.例如：Since the road is wet, it must have rained last night.He can’t have missed the way. I drew him a map.“The dictionary has disappeared. Who could have taken it?”当然对现在发生或将来发生的事情,要用must do 表示猜测, 否定为c an’t do.He must understand that we mean business.You must be hungry after a long walk.2.may / might have donemay / might have done 表示推测过去某事“也许”发生了.may 比 might 表示的可能性在说话人看来稍大些。
例如：I can’t find my keys. I may / might have left them at the s chool yesterday.3. could have done 在肯定句型中, 往往用作委婉的批评. 本应该做什么,而没做; 有时也用作猜测.You could have told us earlier.Tom could have taken the dictionary.4. ought to / should have done和ought not to / shouldn’t have doneought to / should have done 和 ought not to / shouldn’t have done 用于对已发生的情况表示“责备”、“不满”，分别表示“本应该…”和“本不应该…”。