Unit3 语法专项课件-现在完成时 2025-2026学年冀教版英语八年级下册

教学课件 冀教英语八年级下册 Unit3 语法专项—— 现在完成时 全解精讲+分层练习 1 学习目标 1.掌握现在完成时的定义、基本结构 2.熟练运用现在完成时三种核心用法 3.牢记规则与不规则动词过去分词变化 4.能准确识别现在完成时时间标志词 5.会做单选、填空、句型转换等各类题型 现在完成时 定义 含义1：过去发生的动作，对现在产生了影响或留下了某种结果 含义2：过去开始的动作或状态，一直持续到现在，可能还会继续下去 特点：强调现在的结果/状态，不强调过去动作发生的具体时间（无明确过去时间状语） 使用场景：常和不确定的过去时间连用，无法明确说出动作“具体何时发生”，只关注与现在的关联 基本结构 总述 1.结构：助动词 have / has + 动词过去分词（ done) 2.助动词选择：主语为he/she/it/单数名词/不可数名词时，用has（单三搭配has）主语为I/you/we/they/复数名词时，用have（非单三搭配have） 4.句式变化规律：所有句式（肯定、否定、疑问）都围绕“助动词have/has + 过去分词”展开，仅调整助动词位置或添加not 肯定句结构 结构：主语 + have/has + 动词过去分词 例句1：We have finished our homework. 例句2：She has visited the Great Wall. 记忆口诀：单三has，其余have，后面紧跟过去分词，动作结果/状态留到现在 说明：两种情况——动作已完成（对现在有影响）、状态持续到现在 否定句结构 结构：主语 + have/has + not + 动词过去分词 缩写：haven’t = have not；hasn’t = has not 例句1：They haven’t seen the film.=They have not seen the film. 例句2：He hasn’t come back yet.=He has not come back yet. 易错提醒：not必须放在have/has之后、过去分词之前，不能说“have not done”以外的顺序（如don’t have done错误） 一般疑问句结构 结构：Have/Has + 主语 + 动词过去分词？ 肯定回答：Yes, 主语 + have/has. 否定回答：No, 主语 + haven’t/hasn’t. 例句1：—Have you read this book? —Yes, I have. 例句2：—Has he left? —No, he hasn’t. 特殊疑问句结构 结构：疑问词 + Have/Has + 主语 + 动词过去分词？ 常用疑问词及用法：what（问动作内容）、who（问人）、where（问地点）、how long（问持续时间，最常考） 例句1：What have you done today? 例句2：How long has she lived here? 易错提醒：疑问词后用Have/Has开头的疑问句语序，不用陈述句语序 have 与 has 用法区分 主语类型 助动词 例句（结合现在完成时） I/you/we/they/复数名词 have They have left.（他们已经离开了，现在不在这儿） he/she/it/单数名词 has She has gone.（她已经走了，现在还没回来） 不可数名词（如water, time） has Water has become ice.（水已经变成冰了，现在是冰的状态） 指示代词this/that（表单数） has That has helped me.（那件事帮到我了，现在我受益） 用法1：过去动作→现在影响 1.核心逻辑：过去某个时间做了动作，动作已经结束，但现在有明确结果，结果是重点 2.高频标志词：already（已经，肯定句中常放于过去分词前）、just（刚刚，放于过去分词前）、yet（还/已经，否定句/疑问句放句末）、ever（曾经，疑问句中）、never（从不，否定句中） 例句1：I have lost my key. 例句2：She has just arrived. 用法2：过去开始→持续到现在 1.核心逻辑：动作或状态从过去某个时间点开始，一直延续到现在，可能继续延续，也可能刚结束 2.高频标志词：for + 时间段 ；since + 时间点/一般过去时从句 例句1：He has lived here for 10 years. 例句2：We have known each other since 2020. 关键提醒： 动词必须用延续性动词（如live, know, work） 用法3：过去不确定时间经历 1.核心逻辑：表示“曾经做过/从未做过”某事，强调“经历”本身，不强调动作发生的具体时间、地点或过程 2.高频标志词：ever（曾经，用于一般疑问句，询问是否有过某种经历）、never（从不，否定句，表没有过某种经历）、before（以前，放句末）、once（曾经，表“一次”） 例句1：Have you ever been to Beijing? 规则动词过去分词 变化 1.一般情况：直接在动词词尾加-ed → play-played、work-worked、 2.以e结尾的动词：直接在词尾加-d → live-lived、like-liked、love-loved 3.以“辅音字母 + y”结尾的动词：先变y为i，再加-ed → study-studied、carry-carried、try-tried（注意：元音字母+y结尾不变，如play-played） 4.重读闭音节结尾的动词（辅+元+辅，且末尾只有一个辅音字母）：双写末尾的辅音字母，再加-ed → stop-stopped、plan-planned 不规则动词过去分词（必背） 1.be → been ；go → gone 2.do → done ；have → had 3.see → seen ；eat → eaten 4.win → won ；write → written 5.come → come ；take → taken 6. begin→begun、drink→drunk、break→broken、speak→spoken 已完成类 标志词 1.already：已经，用于肯定句，可放于过去分词前或句末 2.yet：还/已经，用于否定句和疑问句 ，只能放于句末 3.just：刚刚，用于肯定句，放于助动词have/has和过去分词之间 4.ever：曾经，用于一般疑问句，放于主语和过去分词之间 5.never：从不，用于否定句，放于助动词have/has和过去分词之间；before：以前，放于句末 持续类 标志词 1.for + 时间段：表示动作持续的时长，后面接具体的时间长度 2.since + 时间点：表示动作开始的时间，后面接具体的时间点 3.so far：到目前为止，用于肯定句或否定句 4.in the last/past few years：近几年，固定搭配，用于现在完成时，表“最近几年发生的动作，持续到现在” 5.up to now：直到现在，和so far用法一致，可互换 现在完成时 易错点1 核心易错点：现在完成时不能和确定的过去时间状语连用 错误例句：I have seen him yesterday. 正确改写：I saw him yesterday. 正确例句：I have seen him before. 常见易错时间词：yesterday（昨天）、last week（上周）、last year（去年）、just now（刚才），出现这些词，一定用一般过去时 现在完成时 易错点2 1.核心易错点：for/since引导的持续类句子中，必须用延续性动词，不能用短暂动词（短暂动词不能持续） 错误例句：He has left for 2 hours. 正确改写：He has been away for 2 hours.（be away是延续性短语，可表示“离开”的状态持续） 高频替换（必记）：leave→be away、buy→have、borrow→keep 一般过去时 vs 现在完成时 1.一般过去时：核心是描述过去发生的动作，只关注过去，不涉及现在，常带确定过去时间状语 2.现在完成时：核心是强调过去动作对现在的影响，或动作持续到现在，不带确定过去时间状语 过去时例句：I finished it yesterday. 完成时例句：I have finished it. 课堂小练 单选 1.My mother ______ cooking already. A. finishes B. finished C. has finished 2.They ______ in this city since 2019. A. live B. lived C. have lived 3.______ you ever ______ to a sports camp? A. Did; go B. Have; been C. Are; going 4.We ______ never ______ that movie before. A. have; seen B. did; see C. will; see 5.She ______ in Beijing for 15 years. A. works B. worked C. has worked 6.He ______ just ______ his homework. A. have; finished B. has; finished C. is; finishing C C B A C B 课堂小练 用所给词适当形式填空 1.I ______________ (read) this book twice. 2.They ______________ (not visit) the museum yet. 3.He ______________ (be) a teacher since 2015. 4.__________ you __________ (see) my pen? 5.We ______________ (live) here for 8 years. have read haven’t visited has been Have seen have lived 课堂小练 用所给词适当形式填空 1.She _______________ (not finish) her work so far. 2.____________ he ____________ (meet) the famous player? 3.They ____________ (make) great progress in recent years. 4.I ____________ never ____________ (ride) a horse. 5.It ____________ (rain) for three hours. hasn’t finished Has met have made have ridden has rained 句型转换 肯定→否定 1.We have cleaned the classroom. → We __________ __________ the classroom. 2.He has called his parents. → He __________ _________ his parents. 3.They have watched the game. → They __________ ___________ the game. haven’t cleaned hasn’t called haven’t watched 句型转换 肯定→一般疑问 1.I have finished my homework. → __________ you _________ your homework? 2.She has been to London. → __________ she __________ to London? 3.We have learned English for 6 years. → __________ you __________ English for 6 years? Have finished Has been Have learned 句型转换 对划线部分提问 1.I have stayed here for two weeks.（划线for two weeks） → _________ __________ have you stayed here? 1.They have bought a new car.（划线a new car） → __________ have they bought? 1.She has taught in this school since 2018.（划线since 2018） → _________ _________ has she taught here? How long What How long 判断句子正误并改正（1） 1.I have seen him yesterday. 2.He has left for two hours. 3.Have you ever watch this show? 4.We have make much progress this term. 5.She has been here since 5 years. 错→I saw him yesterday. 错→He has been away for two hours. 错→Have you ever watched this show? 错→We have made much progress this term. 错→She has been here for 5 years. 判断句子正误并改正（2） 1.They has visited the Great Wall. 2.Have you ever been to Beijing? 3.I haven’t finished my homework yet. 4.He have lived here for ten years. 5.We saw that film many times. 错→They have visited the Great Wall. 对 对 错→He has lived here for ten years. 错→We have seen that film many times. 知识总结 1.核心结构：have/has + 动词过去分词 2.三种用法：① 过去动作→现在影响（标志词already/just/yet）；② 过去开始→持续至今（标志词for/since）；③ 过去不确定时间经历（标志词ever/never） 3.重点标志词：already/yet/just/ever/never（已完成类）；for/since/so far/in the past few years（持续类） 4.关键注意：不与确定过去时间（yesterday/last week）连用；for/since句用延续性动词，避免短暂动词 5.核心区分：一般过去时谈“过去动作”，现在完成时谈“过去动作对现在的影响/持续状态” 教学课件 Unit3 语法专项—— 现在完成时 Thank you for listening! 29 $