情态动词 can could should ought to must-2025-2026学年七年级英语下册语法知识点全解（译林牛津版）

初一下译林牛津版 【语法专版】 A版知识点全解 语法专版 【专题】情态动词can/could/should/ought to/must 语法专项突破 考频分析 初一下译林牛津版中，情态动词can/could/should/ought to/must是基础语法模块，考频占词法总量的 15%左右，主要分布在试卷核心题型：单项选择3-4题、完形填空2-3题、语法填空1-2题、书面 表达（基础考察，影响句子语气与意图表达准确性）。在语境理解类题日中，情态动词的语气辨析、 用法差异及语境匹配往往是解题关键。 考查内容 。基础词义辨析：can(能力/许可)、could(过去能力/委婉请求)、should(建议/义务)、ought to(责 任/劝告)、ust(必须/推测)的核心语义区分 。语境应用差异：口语交际中委婉请求(could)、责任义务(should/ought to)、强制要求(nust)的 场景匹配，以及can表推测用于否定句/疑问句的规则 ·句式转换规则：含情态动词的陈述句变疑问句/否定句（如mustn't禁止vs needn't不必），以及与被 动语态结合(sth.must be done)的结构 知识点一：情态动词can/could/.should/ought to/must的用法 l.can(表能力或许可，口语中更常用) 。含义及用法：表示“能，会”（能力）或“可以”（许可），否定形式为cat(不能/不允许) ·例句： 1.I can speak English.（表能力) 2.You can go home now.(表许可) 2.could(can的过去式，或表委婉语气) 。含义及用法：表示过去的能力，或用于现在时中提出请求/疑问，语气比cn更委婉 初一下译林牛津版 【语法专版】 A版知识点全解 。例句： l.She could swim when she was five.(过去的能力) 2.Could you help me?(委婉请求，现在时) 3.should(表建议或义务) ·含义及用法：表示“应该”，用于提出建议或表达责任义务，否定形式为shouldr't(不应该) 。例句： 1.You should study hard.(表建议) 2.We should respect our parents..(表义务) 4.ought to(表应该，语气比should稍正式) 。含义及用法：与should用法相近，后接动词原形，否定形式为ought not to ·例句： 1.You ought to follow the rules.(表应该) 2.He ought not to be late.(否定式) 5.must(表必须或肯定推测) ●含义及用法：表示“必须”（主观义务）或“一定”（肯定推测），否定形式为ust't(禁止) ·例句： l.You must finish your homework first.(表必须) 2.He must be at home now.(肯定推测) 知识点二：情态动词can/could/should/ought to/must的基本用法和区别 1.can(能力、许可、可能性) ·核心含义：表示“能/会（能力）”“可以（许可，口语中）”“可能（推测，用于否定句/疑问句）” ·基本结构：主语+can+动词原形（无人称变化，否定式为can't/cannot) ·例句： 1.She can speak English fluently.(能力：她能流利说英语) 2.Can I borrow your pen?(许可：我可以借你的笔吗？) 3.It can't be true.(可能性否定：这不可能是真的) 初一下译林牛津版 【语法专版】 A版知识点全解 2.could(过去能力、委婉请求、可能性) ·核心含义：can的过去式（过去能力）：委婉请求（比can更礼貌）：较小可能性（用于肯定句/否定 句/疑问句) 。基本结构：主语+could+动词原形（无人称变化，否定式为couldn't) ·例句： l.I could swim when I was five.(过去能力：我五岁时会游泳) 2.Could you please open the window?(委婉请求：您能打开窗户吗？) 3.This book could be helpful.(可能性：这本书可能有帮助) 3.should(建议、义务、推测) ·核心含义：表示“应该（建议/义务）”“按理说（推测）” 。基本结构：主语+should+动词原形（无人称变化，否定式为shouldn't) ·例句： l.You should study hard for the exam.(建议：你应该为考试努力学习) 2.He should be at home now.(推测：他现在按理说应该在家) 4.ought to(义务、责任，语气比should稍强) ·核心含义：表示“应该（强调义务/责任，与should用法相近，后接todo)” 。基本结构：主语+ought to+动词原形（否定式为ought not to/oughtn'tto) 。例句： 1.We ought to respect our parents.（义务：我们应该尊敬父母) 2.You ought not to smoke in public.（否定：你不应该在公共场合吸烟) 5.must(必须、肯定推测) ·核心含义：表示“必须（主观义务，语气最强）”“一定（肯定推测，用于肯定句）” 。基本结构：主语+must+动词原形（无人称变化，否定式为mustn't“禁止”needn't“不必”） ·例句： 1.You must wear a seatbelt when driving.(必须：开车时必须系安全带) 2.She must be happy with the result..(肯定推测：她一定对结果很满意) 3.You mustn't play with fire.（禁止：你不许玩火) 4.一Must I finish it today?一No,you needn't.(不必：一我今天必须完成吗？一不，你不必) 3 初一下译林牛津版 【语法专版】 A版知识点全解 知识点三：情态动词can/could/should/ought to/must 1.can(能/会/可) 。基础用法拓展（中考必背）： 1.表能力（能/会）一例句：She can speak three languages. 2.表许可（可以）→例句：Can I borrow your per? 3.表可能性（常用于否定句/疑问句）→例句：It can’t be true.. 4.固定句型：can't help doing（忍不住做)→例句：Ican't help laughing when I see him. 2.could(能/会/可以，can的过去式/委婉语气) 。基础用法拓展（中考必背）： l.表过去能力（过去能/会）→例句：He could swim when he was five.. 2.表委婉请求（比can更礼貌）→例句：Could you please pass the book? 3.表推测（可能性比can小）→例句：This could be the right answer. 3.should(应该/应当) 。基础用法拓展（中考必背）： l.表建议（应该）→例句：You should study hard for the exam. 2.表责任/义务（应当）→例句：We should help each other.. 3.表推测（理应）→例句：He should be at home now. 4.固定句型：should+have done(本应该做却未做)一→例句：You should have told me earlier. 4.ought to(应该/应当，语气比should稍强) 。基础用法拓展（中考必背）： l.表责任/义务（应该）→例句：We ought to respect our parents, 2.表推测（理应）→例句：The train ought to arrive on time. 5.must(必须/一定) ·基础用法拓展（中考必背）： 1.表必须（主观要求）→例句：You must finish your homework today. 2.表禁止(mustn’t,不许)→例句：You mustn’t play with fire 3.表推测（肯定，用于肯定句）→例句：He must be in the library. 4.固定搭配：must have done(一定做过某事)→例句：She must have arrived home. 4 初一下译林牛津版 【语法专版】 A版知识点全解 考法精析 考法一：can/could表能力与委婉语气辨析 核心：根据语境判断can/could表示”能力”还是”委婉请求”，注意could表委婉时回答用can 真题1（语法填空)： She(swim)very well when she was ten years old. 答案：could 解析：由时间标志词'when she was ten years old,可知表示过去的能力，用can的过去式could。 真题2（单项选择)： -you please pass me the dictionary? -Sure,here you are. A Can B Could C Must D Should 答案：B 解析：根据语境”请求递字典”可知需用委婉语气，could用于现在时表委婉请求，符合题意。 考法二：情态动词用法辨析 核心：根据语境判断情态动词表能力、许可、建议、义务、推测等含义，选择正确情态动词 真题1（语法填空）： Yoube quiet in the library.It's a rule for everyone. 答案：must 解析：由“it's a rule”可知表示必须遵守的规定，用must表必须。 真题2（完形填空)： -you help me carry this box?It's too heavy. -Sure,no problem. A.Must B.Should C.Could D.Ought to 答案：C 解析：根据语境可知是提出请求，且语气委婉，用Could。 考法三：情态动词的综合辨析与语境运用 核心：结合语境区分can/could/should/ought to./must的语气差异及用法，包括能力、许可、建议、义 务、推测等场景 真题1（单项选择）： -you help me carry this heavy box? -Sorry,I lift it.It's too heavy for me. A.Can;can't B.Must;needn't C.Should,shouldn't D.Ought to;ought not to 答案：A 解析：第一空表示委婉请求，用Can;第二空根据“Sorry”和“too heavy”可知表示“不能”，用 can't。Must表必须，needn't表不必；Should和ought to表应该，语气不符。 5 初一下译林牛津版 【语法专版】 A版知识点全解 真题2（语法填空)： You_(must/should)brush your teeth twice a day.It's good for your health.And you(can't/mustn' t)eat too much candy. 答案：should;mustn't 解析：第一空表示建议“应该”刷牙，用should(must语气过于强硬，日常建议用should更合适)： 第二空表示“禁止”吃太多糖，用mustn't(can’t表不能，此处强调禁止的义务)。 解题小妙招 情态动词妙招 can表能力或许可，could过去委婉请： 委婉请求用could,回答用can要记清： must表必须或肯定，规则推测常用它； should ought to表建议，ought to语气更强些； 语境分析是核心，含义功能先辨明： 请求委婉could佳，能力过去could行： 义务规则用must,建议应该should灵。 真题演练 演练一：单项选择（共10题） 1.We_follow traffic rules to keep safe on the road. A Can B Should C Could D May 2.一_you speak French? 一No,Ican't,butI一speak English well. A Can;can B Must;should C Should;must D Could;ought to 3.Yousmoke in the hospital.It's dangerous for patients. A mustn't B needn't C shouldn't D can't 4.-I borrow your ruler?Mine is broken. -Sure,here you are. A Must B Should C Could D Ought to 5.The girl swim when she was six,so she joined the swimming club. A can B could C must D should 6.He_be at school now.The bell for class has already rung A must B can C might D should 7.You_finish your homework before watching TV.It's a good habit. A can B must C could D may 6 初一下译林牛津版 【语法专版】 A版知识点全解 8.-Must I return the book today? -No,you_.You can keep it for three more days. A mustn't B needn't C can'tD shouldn't 9.If you want to pass the exam,you-study harder than before. A should B can C could D may 10.-you help me carry the heavy box? -Of course.Let's go. A Must B Should C Could D Ought to 演练二：填空试题（共10题） 1.You_(应该)listen to your parents'advice. 2.She()play the piano very well when she was five. 3.We_(必须)wear uniforms at school on weekdays. 4.一_（能）you open the window.,please?It's hot here. -Sure. 5.He-(禁止)park his car here..Thre'sa“No Parking”sign, 6.You (eat too much junk food.It's bad for health. 7.The door is open.They-(一定)be at home now. 8.I-(不会)swin,so I never go to the deep pool.. 9.You()leave the classroom after finishing the test. lO.We一（应该）protect the environment to make the earth cleaner. 演练三：语法填空（共10空） Tom is a middle school student.He 1.-(can)play basketball very well,so he is on the school team.Every morning,he 2.-(must)get up at 6:30 to practice,because the coach says,"You 3.-(should)work hard if you want to win the game." Last week,Tom had a cold.His mother said,"You 4.-(mustn't)go to practice today.You need to rest. Tom felt sad,but he knew his mother was right.He 5.-(could)only stay at home and read books. This afternoon,Tom's friend Mike called him:"6.(Could)you come to the park?We're playing games!Tom said,"I'm sorry,I 7.-(can't).I 8.-(have to)finish my homework first." Mike understood and said,"Okay.Then we9.-(should)meet tomorrow after school."Tom smiled and replied,"Great!I 10.(must)be there on time!" 7 初一下译林牛津版 【语法专版】 A版知识点全解 答案区 演练-：1B2.A3.A4.C5B6.A7B8.B9.A10.C 1.should/ought to 2.could 3.must 4.Could 5.mustn't 6.shouldn't 7.must 8.can't 9.can 10.ought o 演练三：1.can2.must3.should4.mustn't5.could6.Could7.can't8 have to9.should10.must P