英语情态动词知识总结

一、核心规则情态动词 动词原形不能加 to不能加 ing不能加 ed✅ Shecan swim.❌ Shecan swims.❌ Shecan to swim.❌ Shecan swimming.二、英语里有哪些情态动词共9个核心情态动词中文意思例子can能/会Icandrive.could可以/能够过去/委婉Shecouldread when she was 4.will将/会Hewillcome tomorrow.would会/愿意过去/委婉Iwouldlike some tea.shall将第一人称英式/正式Ishallreturn.should应该Youshouldsee a doctor.may可以/可能MayI come in?might可能比 may 不确定Itmightrain.must必须Youmusttell the truth.另外还有ought to应该但它后面跟to算是半情态动词。三、为什么后面要跟动词原形因为情态动词本身已经携带了“时态”和“人称”的信息不需要动词再变形。can已经表达了“能力/可能”不需要动词加swill已经表达了“将来”不需要动词加edmust已经表达了“必须”不需要动词加ing对比普通动词✅ Herunsevery day.run 加 s因为主语是第三人称✅ Hecan runevery day.can 后面不能用 runs四、最容易犯的错误❌ 错误1情态动词后面加to错误正确I cantoswim.I can swim.You musttogo.You must go.She willtocome.She will come.⚠️唯一例外ought toShe oughttogo.❌ 错误2情态动词后面加s错误正确He canswims.He can swim.She willgoes.She will go.It mustworks.It must work.❌ 错误3情态动词后面加ing/ed错误正确I canswimming.I can swim.You mustfinished.You must finish.五、情态动词的否定形式直接在情态动词后面加not后面的动词仍然是原形。肯定否定I can swim.Icannot/cantswim.She will come.Shewill not/wontcome.You must go.Youmust not/mustntgo.He should try.Heshould not/shouldnttry.⚠️must not表示“禁止”不是“不必”。“不必”用dont have to。六、情态动词的疑问句直接把情态动词提到主语前面后面的动词仍然是原形。陈述句疑问句I can help.CanI help?She will come.Willshe come?You should go.ShouldI go?He must leave.Musthe leave?七、容易混淆的对比1️⃣ can vs be able to情态动词短语动词can 原形只有现在时be able to 原形有时态变化✅ Icanswim.✅ Iwill be able toswim next week.can 没有将来时✅ Ihave been able toswim since I was 5.can 没有完成时规律can只能用在现在时和过去时could其他时态用be able to。2️⃣ will vs be going to情态动词短语will 原形临时决定/预测be going to 原形计划好✅ The phone is ringing. Iwillanswer it.临时✅ Iam going tovisit my mom tomorrow.计划3️⃣ must vs have to情态动词短语动词must 原形主观/说话人的要求have to 原形客观/外部规则✅ Imustfinish this report.我自己觉得必须✅ Ihave towear a uniform at work.公司规定must没有过去时和将来时过去时用had to。八、情态动词的“推测”用法情态动词推测程度例子must几乎肯定90%Shemustbe home. The light is on.will很可能80%Hewillbe at work now.would推测70%Thatwouldbe John at the door.should按理应该70%The trainshouldarrive soon.may可能50%Itmayrain later.might有可能40%Shemightbe late.could可能30-40%Hecouldbe stuck in traffic.cant不可能否定Thatcantbe true.九、自测题She ______ speak three languages. (can / cans)He ______ to come tomorrow. (will / will not)You ______ to call me. (must / must not) → 选“禁止”的意思______ I help you? (May / Will)I ______ to finish this today. (must / have)She ______ be at home. The lights are off. (must / cant)They ______ to the party tonight. (will go / will goes)答案canwill not/wontwill 后面跟原形 come不是 to comemust not禁止May请求许可havehave tocant不可能will gowill 原形十、总结情态动词 9个核心词 can / could / will / would / shall / should / may / might / must 规则情态动词 动词原形 ❌ 不加 to ❌ 不加 s ❌ 不加 ing ❌ 不加 ed 否定情态动词 not 原形 疑问情态动词 主语 原形