情态动词表过去的能力和请求-2025-2026学年八年级英语下册语法知识点全解（仁爱版）

初二下仁爱版 【语法专版】 情态动词全解 语法专版 【专题】情态动词（表过去的能力和请求） 核心语法突破 考频分析 初二下仁爱版中，情态动词（表过去的能力和请求）是重点语法模块，考频占情态动词考点总量的 30%左右，主要分布在核心题型：单项选择(1-2题)、完形填空(2-3题)、语法填空(1-2题)、阅 读理解(1-2题)。在语境理解类题目中，情态动词的过去式形式（如coud)及表意区别往往是解 题关键。 考查内容 ·过去能力表达：can的过去式could表示过去具备的能力，与was/were able to的语境差异（如描述 过去成功完成某动作时多用was/were able to) 。过去请求表达：could/would用于委婉提出过去的请求，区分can/mnay与could/would在请求语境中 的时态差异及语气委婉程度（如Could you help me yesterday?中could表过去请求，而Can you help me?表现在请求) 知识点一：情态动词（表过去的能力和请求） 1.表过去的能力(could) 1.用法：表示过去具备的能力，相当于“过去能够做某事” 2.例句： 。She could swim when she was five.(她五岁时就会游泳了。) ·My father could speak English well ten years ago.(我爸爸十年前英语说得很好。) 2.表过去的请求(could/would) 1.could用法：语气委婉，用于过去向他人提出请求，回答时常用can/may 2.例句： ·Could you help me carry the box yesterday?(昨天你能帮我搬箱子吗？) 1 初二下仁爱版 【语法专版】 情态动词全解 ·She asked if she could use my pen.(她问是否能用我的钢笔。) 3.would用法：用于第二人称，表示过去习惯性的请求或意愿，语气比could更委婉礼貌 4.例句： ·Would you please pass me the salt just now?(刚才请你把盐递给我好吗？) ·My mother would often ask me to clean my room when I was young.(我小时候妈妈常常让我打扫 房间。) 知识点二：情态动词（表过去的能力和请求） l.情态动词can/could表过去的能力 1.基本用法 。can表现在或一般的能力，could表过去的能力（强调过去具备的能力，不涉及现在） 2.结构与例句： 。过去能力肯定句：主语+could+动词原形 例句：She could swim when she was five.(她五岁时就会游泳了。) 。过去能力否定句：主语+couldn't(could not)+动词原形 例句：I couldn't ride a bike last year.(我去年还不会骑自行车。) ·过去能力疑问句：Could+主语+动词原形？ 例句：Could you speak English when you were in primary school？(你小学时会说英语吗？) 2.情态动词could表过去的委婉请求 1.基本用法：could用于过去时态中，比can更委婉地表达请求，常用于疑问句，回答时通常用can或 could(肯定)、can't或couldn't(否定) 2.结构与例句： ·请求句：Cold+主语+动词原形？ 例句：Could you help me with my homework yesterday?(昨天你能帮我辅导作业吗？) 。肯定▣答：Sure,Ican/could./Of course. 例句：一Could you pass the pen to me just now？(刚才你能把笔递给我吗？)Sure,here you are. (当然，给你。) 。否定▣答：Soy,Ican't/couldn't. 例句：一Could you go shopping with me an hour ago？(一小时前你能和我去购物吗？)Sory,I couldn't.I was busy.(对不起，我不能。我当时很忙。) 初二下仁爱版 【语法专版】 情态动词全解 知识点三：情态动词（表过去的能力和请求） 1.could(表过去的能力) 1.基础用法（中考必背)： 。表示过去具备的能力→例句：She could swim when she was five.(她五岁时就会游泳了。) ●否定式couldn't表过去没有能力→例句：I couldn't ride a bike last year.(去年我还不会骑自行 车。) 。与表示过去的时间状语连用→例句：He could speak English well when he was in primary school. (他小学时英语就能说得很好。) 。委婉询问过去的能力（可与was/were able to互换）→例句：Could you play the piano when you were young?（你小时候会弹钢琴吗？) 2.could(表过去的委婉请求) 1.日常场景搭配（中考常考)： 。向他人提出过去的请求（语气委婉）→例句：Could you help me with my homework yesterday? (昨天你能帮我辅导作业吗？) 。否定请求用couldn't→例句：I couldn't borrow your pen this momning because you weren'there..(今 天早上我没能借到你的钢笔，因为你不在。) 。回答过去请求的常用句式→肯定：Sure,I could.(当然可以。)否定：Sory,I couldn't.(对不起， 我不能。) 。过去请求的礼貌表达（后接动词原形）→例句：She asked if she could use my dictionary just now. (她刚才问能否用一下我的字典。) 3.was/were able to(表过去成功做到的能力) 1.区别于could的特殊用法（中考易错)： 。强调过去通过努力成功完成某事→例句：He was able to pass the exam after studying hard.(他努 力学习后成功通过了考试。) ·否定式wasn't/weren't able to表过去未能做到→例句：They weren't able to catch the early bus yesterday.(昨天他们没能赶上早班车。) ·不可与表反复性能力的could互换→例句：She could sing well when she was young.(她年轻时 唱歌就很好。)（表反复能力）→She was able to sing a song at the party last night.(她昨晚在派对 上成功唱了一首歌。)（表一次性成功） 解题小妙招 3 初二下仁爱版 【语法专版】 情态动词全解 情态动词解题妙招 推测先看肯否定，语境判断可能性： must表肯定可能性高，can't否定推测最常用： may might可能性较低，根据语境细辨析。 义务推测要分清，义务must表必须： have to强调客观需，should建议要记牢； nustn't意为禁止做，这些用法要记清。 综合运用看语境，能力过去用could: 现在能力用can,请求could更委婉； 不同用法细区分，语气时态要注意。 考法精析 考法一：情态动词表推测(must/can't/may/might)辨析 核心：根据语境判断推测的肯定/否定语气及可能性大小，选择正确情态动词 真题1（语法填空）： The man is wearing a doctor's coat.He_be a doctor. 答案：must 解析：由“穿着医生外套”这一语境可知，对“是医生”的推测可能性极高，用ust表“一定”。 真题2（单项选择)： -Where is Lucy? -She_be in the library.I saw her there just now. A.must B.can't C.may D.might 答案：A 解析：由“刚才在图书馆看到她”可知，对“现在在图书馆”的推测可能性极高，用ust表“ 定”；can't表“不可能”，may/might表“可能”（可能性低于must),均不符合语境。 考法二：情态动词表推测与义务辨析 核心：根据语境区分情态动词表推测(must/cam't/may/might)和表义务(must/have to/should/mustn't) 的用法 真题1（单项选择）： Yoube quiet in the library.Everyone is reading. A must B can't C may D might 答案：A 解析：句意为“你在图书馆必须保持安静，大家都在看书”，此处表义务“必须”，用ust。 4 初二下仁爱版 【语法专版】 情态动词全解 真题2（语法填空)： The girl in red_be Lucy.She has gone to Beijing.(提示：填表推测的词) 答案：can't 解析：由“她去北京了”可知，穿红衣服的女孩“不可能”是Lucy,表否定推测用cant。 考法三：情态动词表过去能力、请求及推测的综合运用 核心：结合语境区分情态动词could表过去能力、委婉请求与must have done/can't have done等表 过去推测的用法，掌握不同功能的句式结构及回答逻辑 真题1（单项选择)： -you swim across the river when you were 10? -No,I_.But now Ido it easily. A.Could;couldn't;can B.Can;can't;could C.May,mustn't;might D.Must;needn't;should 答案：A 解析：第一空根据"when you were 10'表过去能力，用Could:第二空否定过去能力用couldn't:第 三空now”表现在能力用can。 真题2（语法填空)： The door was locked.He(must/forget)to take the key.Hismother(ask)him to bring it this morning, but he was in a hurry. 答案：must have forgotten,could/would 解析：第一句根据”门是锁着的'表对过去的肯定推测，用must have forgotten;第二句'this morning” 表过去习惯性请求，用could或would.,符合”过去委婉请求或意愿的用法。 真题演练 演练一：单项选择 1.My grandfatherplay chess very well when he was young. A must B could C can D should 2.-you please pass me the ruler just now? -Sure,here you are. A Must B Should C Would D May 3.The light is off.He be at home now. A must B may C can't D might 5 初二下仁爱版 【语法专版】 情态动词全解 4.You follow the traffic rules when crossing the street.It's important. A must B may C can D might 5.-I use your dictionary for a minute? -Yes,you can. A Must B Should C Could D Need 6.You_come early tomorrow.The meeting starts at 10 a.m. A needn't B mustn't C can'tD shouldn't 7.The ground is dry.It rained last night. A must have B can't have C may have D might have 8.Shefinish her homework before dinner yesterday.Her mom asked her to. A has to B had to C must D should 9.-Where is Tom? -He_be in the classroom.I saw him there five minutes ago. A must B can't C may D might 10.Youwear a seat belt when driving.It's the law. A would B could C must D may 演练二：填空 1.My sister_(can)ride a bike when she was six years old. 2.(would)you like to help me carry these books yesterday? 3.The book-(must)be Mary's.It has her name on it. 4.You_(mustn't)talk loudly in the library. 5.-(may)I borrow your pen?I need to write something. 6.They(don't have to)go to school tomorrow.It's a holiday. 7.The door is locked.He(can't)be at home. 8.She(should)brush her teeth twice a day to keep healthy. 9.You(needn't)buy me a gift.Your visit is enough. 10.The sky is dark.It(may)rain this afternoon. 演练三：语法填空 Tom is a student in Grade 8.Last year,he 1-(could)not swim at all.His father taught him every weekend, and now he 2(can)swim very well.Yesterday,his friend Lily asked,"3-(could)you teach me to swim this Sunday?"Tom said yes. 6 初二下仁爱版 【语法专版】 情态动词全解 Tom'smom often tells him,"You 4(must)finish your homework before playing outside."He always follows this rule.But this morning,he 5(have to)leave home early,so he didn't finish his math homework.His teacher said,"You 6(should)finish it after class today." It's 7 p.m.now.Tom is not at home.Where is he?He 7-(must)be at the school library because he of- ten studies there in the evening.He8(can't)be playing outside.Hetold his mom he would study tonight. Last week,Tom lost his new watch.He 9(may have)left it in the classroom.His friend said,"You 10 (should)ask the teacher to help you look for it." 答案区 演练-：1B2.C3.C4.A5.C6.A7.A8.B9.A10.C 演练二：1.could2.Would3.must4 mustn't5May6.don't have to7.can't8.should9.needn't10.may 演练三：1.could2.can3.Could4must5.had to6.should7.must8.cant9 may have10.should 7