情态动词系统复习-2025-2026学年九年级英语下册语法重难点精讲（沪外版）

9年级沪外版 【语法专版】 D版重难点精讲 语法专版 【语法专题】情态动词系统复习专项突破 初中沪外版9年级 语法精讲 语法概述：情态动词(can,may,must,should,.would等)=表示说话人的语气或态度，如能力、许 可、义务、推测等，在句中不能单独作谓语，需与动词原形一起构成谓语。 重难点讲解 重难点一：情态动词can,may,must的基本用法区别讲解： -can表示“能力”“许可”或“可能性”，否定形式为can’t(不能/不可能)。 She can speak three languages.(能力) Can I borrow your pen?(许可，口语中常用) -may表示“许可”（较正式）或“可能性”，否定形式为may not(不允许)。 You may leave the room now.(许可) It may rain tomorrow.(可能性) -must表示“必须”“肯定”（推测），否定形式为mustn’t(禁止)或neen't(不必)。 We must follow the traffic rules.(必须) He must be at home now.(肯定推测) 真题再现： 1.(2024上海浦东期末，沪外版)一I use your dictionary?I left mine at home -Sure,here you are. A.Must B.May C.Need D.Should 答案：B 解析：表示请求许可，用may更正式礼貌，符合语境。 2.(2023江苏苏州期中，沪外版)You play with fire.It's dangerous! A.mustn’t B.needn't C.can’t D.may not 9年级沪外版 【语法专版】 D版重难点精讲 答案：A解析：根据“危险”可知此处表示“禁止”，用mustn’t。 重难点二：情态动词表推测的用法讲解： must用于肯定句，表“肯定推测”（可能性>90%），否定句用can't(不可能)。 The light is on.He must be in the office He can'tbe a doctor-he's only 16. -may/might/could用于肯定句或否定句，表“可能推测”（可能性50%-70%），might/could语气更 弱。 She may be late for the meeting. It might rain this afternoon,but I'm not sure 真题再现： 1.(2024浙江杭州月考，沪外版)-Where is Lucy?Ican't find her. -She be in the library.She often reads there after school. A.must B.can C.may D.need 答案：A解析：根据“她放学后常去图书馆”可知是肯定推测，用ust。 2.(2023 安徽合肥期末，沪外版)Is that Mr.Green? -No,it be him.He has gone to Beijing. A.mustn't B.can’t C.needn't D.may not 答案：B解析：根据“他去北京了”可知“不可能是他”，用can't表否定推测。 重难点三：情态动词“必须”与“不必”的表达讲解： -must表“必须”，其否定“不必”用needn't或don'thave to,.而非mustn't(mustn't表“禁 止”)。 You must finish your homework before dinner.( -Must I hand in the report today?一No,you needn't/don't have to.(不必) -have to表“客观需要”，有人称和时态变化，否定形式为don’t/doesn’t/didn’t have to。 She has to take care ofher little sister every day. 真题再现： 1.(2024广东广州期中，沪外版)一Must we clean the classroom now? -No,you.You can do it after school 9年级沪外版 【语法专版】 D版重难点精讲 A.nustn’t B.needn't C.can't D.shouldn't 答案：B:解析：must的一般疑问句否定回答用needn't,表示“不必”。 2.(2023 湖北武汉期末，沪外版)y mother is ill,soI_stay at home to look after her A.can B.may C.have to D.must 答案：C解析：根据“妈妈生病”可知是“客观需要”，用have to。. 重难点四：情态动词should/ought to的用法讲解： -should/ought to表“应该”（责任、建议），ought to语气略正式，否定形式为shouldn’t/ought not to You should listen to your parents'advice We ought to help people in need. -疑问句中should置于句首，表建议或征求意见。 Should we go to the park this weekend? 真题再现： 1.(2024 四川成都月考，沪外版)You_eat too much junk food.It's bad for your health A.shouldn't B.needn't C.mustn't D.can't 答案：A 解析：根据“对健康有害”可知是“不应该”，用shouldn’t。 2.（2023山东烟台期末，沪外版)一_I tell Tom about the news? -Yes,you should.He will be happy to hear it. A.Must B.Should C.May D.Need 答案：B:解析：答句用should回应，可知问句是should引导的建议疑问句。 重难点五：情态动词had better的用法讲解： -had better(do sth.)表“最好做某事”，否定形式为had better not do sth,无人称变化，缩写为' 3 9年级沪外版 【语法专版】 D版重难点精讲 d better。 You'd better take an umbrella.It's going to rain You'd better not be late for class. 真题再现： 1.(2024福建厦门期中，沪外版)It's getting late.You_go to bed now. A.had better B.must C.may D.can 答案：A解析：根据“很晚了”可知是建议“最好上床睡觉”，用had better。 2.(2023湖南长沙期末，沪外版)You_better not play computer games for too long.It's bad for your eyes. A.had B.would C.should D.could 答案：A 解析：had better not do sth.为固定搭配，表“最好不要做某事”。 易错点综合演练 L单项选择（直击重难点》 1.-I park my bike here?There's no sign saying"No Parking". A.Must B.May C.Need D.Should 2.You tell lies to your parents.It's not honest. A.mustn't B.needn't C.can't D.may not 3.The door is locked.He be at home now.Let's come back later. A.must B.can C.may D.can't 9年级沪外版 【语法专版】 D版重难点精讲 4.-Must I return the book before Friday? -No,you.You can keep it for another three days. A.mustn't B.needn't C.can't D.shouldn't Ⅱ.用所给词的适当形式填空（强化句型结构） 1.You(should)eat so many candies.They are bad for your teeth 2.The light is off.She(must)be in the room.Maybe she went out 3.-we(go)to the concert this weekend? -Good idea!I heard the band is very popular. 4.He(can)swim when he was five years old.He's good at it now. 5.You (had better)not play football in the street.It's dangerous. Ⅲ.短文填空（综合运用情态动词） 用方框中所给情态动词的适当形式填空，使短文完整通顺。（方框：must,may,can,should,can't, needn't,had better) Hi,Tom!You look worried.What's wrong?You 1.talk to someone if you have problems.You 2. _keep them to yourself.That's not good for you.If you don't want to tell your parents,you 3.talk to your best friend.He 4.give you some good advice.Also,you 5.try to relax.You 6.be too stressed.And remember,you 7.always ask me for help.I'm here for you. V.连词成句（聚焦句型结构） 1.be,in,the,he,office,must,now ( 2.I,borrow,your,ruler,may(?) 3.play,we,mustn't,here,football (. 4.you,should,more,exercise,take (. 5.can't,the,answer,he,question,this (. V.按要求改写句子（巩固情态动词用法） l.You must finish your homework before dinner.(改为否定句) 2.She may be at the playground..(改为一般疑问句并作肯定回答) 5 9年级沪外版 【语法专版】 D版重难点精讲 3.He can speak English very well..(对划线部分提问) 4.We should help each other..(改为同义句) 综合演练参考答案 I.单项选择：1B2.A3.D4.B Ⅱ.用所给词的适当形式填空：1.shouldn't2.can't3.Should,go4.could5.had better Ⅲ.短文填空： 1.should 2.mustn't 3.may 4.can 5.should 6.can't 7.can V.连词成句： 1.He must be in the office now. 2.May I borrow your ruler? 3.We mustn't play football here. 4.You should take more exercise. 5.He can't answer this question. V.按要求改写句子： 1.You needn't finish your homework before dinner. 2.May she be at the playground?Yes,she may. 3.How well can he speak English? 4.We ought to help each other. 6