Unit 2 Let's celebrate!-2026-2027学年高中英语语法专项精讲精练必修二（外研版）

Unit 2 Let's celebrate! 语法专项精讲精练 语法概览 女同步语法一：情态动词表许可/理论可能性-can/could/may/might 女同步语法二：情态动词表推测（对现在和过去的推测）-must/cant/couldn't/ may/might 语法精讲精练一 (一)基本定义 情态动词can/could/may/might在表达"许可"和"理论可能性"时，是高考英语语法填 空、完形填空及写作中的高频考点。表许可表示“允许”或“请求允许”，语气强弱不同；表理论 可能性表示“可能发生"，不指具体某次，而是客观上的可能性，语气由强到弱依次为：can> may>could>might。 (二) 核心用法对比（表格） 功能 情态动词 含义与语气 典型例句 考点提示 肯定句中表允许； 直白、非正式 You can go now.(你可以走 疑问句中表请求； 表许可 can 许可；请求允 了。)Can I borrow your 否定句用cannot 许 pen? (我能借你的笔吗？) /can't表“不允 许”。 更委婉、客气 Could I use your phone? 用于请求时比can 地请求许可 (我能用你的电话吗？) 表许可 could 更礼貌；过去时表 (过去时也可 When I was young,I could 表过去允许) stay up late.(过去允许) “會经被允许”。 较正式、客气 在否定回答中常用 You may leave now.(你现在 表许可 的许可（通常 may not但语气 may 可以离开了。)May I come 用于正式场 强；更常见于书面 in？(我可以进来吗？) 合) 或正式口语。 非常委婉、试 现代英语中 表许可 探性的请求 Might I have a word with might表许可已 might (极少用于肯 you?(我能和你说句话吗？) 较少见，多见于极 定许可) 正式或古老语体。 表示“理论上 Accidents can happen at any time.(事故随时可能发 表理论可能 的可能”，常 can 性 生。)It can be cold in 强调“有时候会”， 指一般情况或 不指具体某次。 winter here.(这里冬天可能 客观事实 冷。) The bridge could collapse 表示“过去理 under heavy rain,(桥在大雨 表理论可能 论上的可能” could 性 或“现在不确 中可能坍塌。)He could be 常用于推测，语气 at home now.(他现在可能在 比may弱。 定的可能” 家。) 表示“事实上 She may be in the library. 常用于对现在或未 表理论可能 的可能”，可 (她可能在图书馆。)tmay 来的推测；否定式 性 may 能性较高（约 rain tomorrow,(明天可能下 nay not表示“可 50%) 雨。) 能不”。 表示“很小的 I might go to the party, 常与but'm but'm not sure.(我可能会 表理论可能 可能”，语气 not sure连用； 性 might 去派对，但不确定。)He 最弱（约 否定式might 30%) might have forgotten the not语气更弱。 meeting.(他可能忘了会议。) (三)核心含义区分（易混点） 1.can与may表许可的区别 can:日常口语中最常用，直接但非正式。 may:更正式、礼貌，常用于书面或对长辈、上级的请求。 在否定回答中，cant语气强硬（不允许），may not语气稍弱（可能不允许但更客 气)。 2.can与may表理论可能性的区别 can:强调“客观规律或普逼情况”，不针对具体事件。 O例句：Smoking can cause cancer.(吸烟可能导致癌症。 一一普逼事实) may:强调“具体事件的可能性”，通常有具体语境。 O例句：Smoking may cause cancer for this patient.(吸烟可能对这个病人 致癌。一一具体推测) 3.could与m ight表推测时的语气强弱 could比might可能性略高，常与"有可能”对应；might则更不确定。 在疑问句中推测通常用could,不用may或might。 Q例句：Could he be lying?(他可能在撒谎吗？) Q例句：May he be lying?(x,通常不这样用) 4.否定形式的差异 cant:表示“不可能”（逻辑上否定） ②例句：He can't be serious.(他不可能当真。) may not/might not:表示“可能不”（可能性较低） g例句：He may not come today..(他今天可能不来.) 9例句：He might not have received the message.(他可能没收到消息。) (四)高考高频考点总结 1.许可句中情态动词的选择：根据语境判断语气的正式程度。 考查：Could I..?比Canl..?更礼貌，但回答通常用can或may。 ②例句：-Could I borrow your car? 一Yes,you can.(回答不用could) 2.理论可能性与具体推测的区分：情态动词+be doing/have done结构。 may/might+be doing:推测正在发生。 g例句：She may be waiting for us at the gate. may/might+have done:推测过去发生。 例句：He might have missed the train. 3.否定推测的区分：cant(不可能)vs.may not/might not(何能不)。 例句：That can't be true,(那绝不可能是真的。) 例句：That may not be true.(那可能不是真的。) 4.固定句型： may as well/might as well:倒不如..，（表示建议） 例句：We may as well wait a bit longer.(我们不妨再等一会儿.) It might be that..:可能.… 例句：It might be that he lost his way. 二、专项练习 (一)单项选择（10小题) 从A、B、C、D四个选项中，选出可以填入空白处的最佳选项。 1.- _I use your dictionary for a moment? -Sure,go ahead. A.May B.Must C.Need D.Should 2.You park here.It's a no-parking zone A.may not B.can't C.might not D.needn't 3.According to the weather forecast,the storm arrive tonight,but it's still uncertain A.can B.must C.might D.should 4.When I was a child,I stay up late only on weekends. A.might B.could C.should D.must 5.-Where is Tom? -He be in the classroom,but I'm not sure. A.must B.can C.may D.would 6. I open the window?It's a bit stuffy here. A.Shall B.Must C.Could D.Ought 7.Even the best teacher make a mistake occasionally. A.might not B.can C.must D.shall 8.You have told me earlier.I would have helped you. A.could B.may C.might D.A and C 9.-The book says that this bird live up to 50 years. -That's amazing! A.can B.must C.should D.need 10.If you have finished your work,you leave now A.may B.must C.need D.shall (二)用所给情态动词的适当形式填空(8小题) 用括号内情态动词的正确形式(can/could/may/might)填空，注意时态与语气。 1.- I borrow your bike?(may) -Of course,you(can). 2.1t (may)snow tomorrow,but the forecast says it's unlikely. 3.l (can)swim when I was five years old 4.You (can)be serious!He is the last person to lie. 5. you please pass me the salt?(could) 6.She (might)know the answer,but I doubt it. 7.The experiment (may)fail if we don't control the temperature properly. 8.In ancient times,only nobles (could)enter the palace. (三)篇章语法填空（12小题) 阅读下面短文，在空白处填入适当的情态动词(can/could/may/might)或它们的否定形 式（缩写如cant,could not,may not,might not均可）。每空一词。 Last night,I had a strange dream.In the dream,I was walking through a dark forest.Suddenly,I saw a light ahead.I thought it1(might)be a cottage,but I wasn't sure.As I got closer,I realized that it 2(could)not be a house because there were no windows.I remembered a legend:deep in the forest,there 3(can)be hidden treasures,but they4(may)also be traps. I hesitated.Should I continue?I knew that I5(can)turn back anytime,but curiosity drove me forward.The light turned out to be a lantern hanging on a tree Under the tree was a box.I wondered what6(might)be inside.I opened it cautiously. Inside were old letters.They 7(may)have been written hundreds of years ago,but the ink was still clear.One letter said:"If you are reading this,you8 (may)be the one who will break the spell.But be careful:the spell9(can) also be dangerous."I felt a chill. Just then,I heard a voice:"You 10(can)not escape now!"I woke up with a start.It was just a dream,but I felt that dreams sometimes 11(can)tell us something about real life.Who knows?This dream 12(might)have some meaning after all. 三、参考答案 (一)单项 1.A;2.B;3.C;4.B;5.C;6.C;7.B;8.D;9.A;10.A 选择 (二)用所 给情态动词 1.May can 2.may 3.could 4.can't 5.Could 6.might 7.may 的适当形式 8.could 填空 (三)篇章 1.might 2.could 3.can 4.may 5.could 6.might 7.may 8.may; 语法填空 9.can 10.can 11.can 12.might 语法精讲精练二 (一)基本定义 情态动词表推测是高考英语高频考点，用于说话人对当前或过去发生的情况进行判断，表 达肯定推测、否定推测或可能性推测。常用情态动词包括： must:一定（肯定推测） cant/couldn't:不可能（否定推测） may/might:可能（可能性推测，might语气更弱） 注意：mustn't不用于表推测，它表示“禁止"。 (二)核心用法与结构 推测 时间 结构 含义 示例 对现 must/can't/may/ 对当前情况 He must be at home.(他现在一定在 在 might+动词原形 做出判断 家。) 对过 must/can't/may/ 对过去情况 They must have finished the work. 去 might have done 做出判断 (他们一定已经完成了工作。) ★具体用法对比： 情态动词 现在推测（+do) 过去推测(+have done) 语气强 度 must 一定做某事（肯定） 一定做过某事（肯定） 最强 最强否 can't 不可能做某事（否定） 不可能做过某事（否定） 定 不可能（与cant互换， 但更 不可能做过（与can't have done 较强否 couldn't 委婉) 互换) 定 may 可能做某事（肯定） 可能做过某事（肯定） 中等 可能做过（比may have done更 might 可能（比may更不确定） 较弱 不确定) (三)核心含义区分 1.肯定推测：仅用must 对现在：The lights are on.He must be in the room. 对过去：The ground is wet.It must have rained last night: 2.否定推测：用can't或couldn't(注意：不能用mustn't) 对现在：She can'tbe40;she looks so young. 对过去：He can't have left because his car is still here. 3.可能性推测：用may或might(might语气更不确定) 对现在：He may/might know the answer..(可能知道) 对过去：She may/might have missed the bus.(可能错过了) ★易错点 must表示推测时，否定形式必须用can't或couldn't,而非mustn't。 may not表示“可能不”，而can't表示“不可能”，程度不同。 could在肯定句中也可表推测（可能性低于may),但本讲重点为must/can't/ couldn't/may/might,故could略讲。 (四)高中高频考点总结（附例句） 1.must/can't对现在推测的语境判断 例句：Look at the smile on his face.He must be satisfied with the result 例句：He can't be in the library;it's closed now. 2.情态动词+have done对过去推测的准确使用 例句：She must have studied hard last night;she looks tired, 例句：They can't have finished the report yet;they started only an hour ago 3.may/might与must/can't的语气区分 例句：He might have forgotten the meeting.(可能性较低) 例句：He must have remembered the meeting;he wrote it down.(高度 肯定) 4.否定推测中can't与couldn't的互换 例句：It couldn't be John at the door;he is abroad now.(=can'tbe) 5.假设语气干扰项（如could have done表“本可以做但未做”，与推测不同） 例句：You could have helped him,but you didn't.(非推测，表虚拟) 二、专项练习 (一)单项选择（(10小题) 从A、B、C、D四个选项中，选出可以填入空白处的最佳选项。 1.The phone is ringing.It be Tom.He said he would call me at this time. A.must B.can't C.may D.might 2.-I saw Mary in the library this morning.-You her.She is still on holiday in Beijing. A.must have seen B.can't have seen C.may have seen D.might have seen 3.He be at home now because the lights are off. A.must B.can't C.may D.might 4.The road is wet.It rained last night. A.must B.must have C.can't have D.may have 5.-Where is my umbrella?-You have left it in the classroom.Let's go and check. A.must B.can't C.may D.couldn't 6.He looks very pale.He _be ill. A.must B.can't C.may D.mustn't 7.She have finished the work so quickly;it's too difficult A.must B.can't C.may D.might 8.The door is locked.He have gone out. A.must B.can't C.may D.might 9.I'm not sure,but he come to the party tonight A.must B.can't C.may D.couldn't 10.You have seen a dinosaur;they are extinct. A.must B.can't C.may D.might (二)用适当的情态动词（或其完成式）填空(8小题) 根据句子语境，用must,can't,couldn't,may,might的适当形式（必要时加 have done)填空。 1.The man over there looks familiar.He (be)our new neighbor..(对现 在推测) 2. (leave)my keys on the desk.Ican't find them anywhere.(对过去 推测) 3.She (know)the answer because she studied the topic thoroughly. (对现在肯定推测) 4.They ,(arrive)yesterday;i saw them at the airport.(对过去肯定推测) 5.He (tell)alie;he is an honest person.(对现在否定推测) 6.The exam is very difficult,but you(pass)it with your intelligence. (对过去可能性推测) 7.Look at the dark clouds.It _(rain)soon.(对现在推测，可能性中等) 8.She (finish)her homework yet;she only started an hour ago. 去否定推测) (三)篇章语法填空（12小题) 阅读下面短文，在空白处填入括号内所给动词的适当形式（需情态动词加动词原形或 have done). Last night,I tried to call my friend Mike,but no one answered.He 1. (be)very busy with his project.I thought he 2. (forget)about our appointment.However,this morning he called me and said he 3. (fall)asleep early because he was too tired. Later,I saw a note on his desk.It read:"I 4. (leave)a message on your phone,but I'm not sure if you got it."I checked my phone and found no message.So he 5. (leave)any message;maybe he just imagined it. Anyway,I also remembered that yesterday,his car was in the garage.He 6. __(go)out by bus.But the bus stop is near his home,so he 7. (miss)the bus.Actually,he told me he took a taxi.So he 8._ (take)a taxi after all. From his behavior,I can tell that he 9. (be)an organized person,but sometimes he 10. (make)mistakes.For example,last week he 11 (lose)his wallet,but he said he 12. (put)it in his bag.We all make mistakes sometimes. 三、参考答案 (一)单项 1.A;2.B;3.B;4.B;5.C;6.A;7.B;8.A;9.C;10.B 选择 (二)用适 1.must be 2.may have left /might have left 3.must know 4.must 当的情态动 have arrived 5.can't tell couldn't tell 6.may have passed might 词填空 have passed 7.may rain might rain 8.can't have finished couldn't have finished 1.must be 2.might have forgotten may have forgotten 3.must (三)篇章 have fallen 4.may have left might have left 5.can't have left/ 语法填空 couldn't have left 6.must have gone 7.may have missed might have missed 8.must have taken 9.must be 10.may make /might make 11.may have lost might have lost 12.must have put