Unit2 语法专项—— 时间状语从句 课件2025-2026学年沪外教版英语八年级上册

教学课件 沪外教英语八年级上册 Unit2 语法专项—— 时间状语从句 全解精讲+分层练习 1 学习目标 1.掌握 as soon as 一…就… 的用法与时态 2.掌握 since 自从…以来 的时态规则 3.掌握 until 直到… / not…until 直到…才… 4.能区分三个连词的逻辑差异 5.能正确完成填空、选择、改写、改错 6.能在写作中正确使用时间状语从句 什么是时间状语从句 用一个句子作时间状语，说明动作发生的时间 结构：主句 + 连词 + 从句（从句用陈述语序） 位置：从句可放主句前，也可放主句后 从句在前时，后面加逗号 例：I will call you. + as soon as + I arrive. as soon as 讲解（1） 含义：一……就…… 强调：两个动作紧接着发生 时态规则（将来）： 主句：一般将来时 will do 从句：一般现在时（主将从现） 例句：I will tell you as soon as I know the truth. as soon as 讲解（2） 时态规则（过去）： 主句：一般过去时 从句：一般过去时 例句：He ran out as soon as he heard the noise. 同义表达：the moment, immediately 提示：从句永远不用将来时 since 讲解（1） 含义：自从……以来 强调：动作从过去持续到现在 时态固定搭配： 主句：现在完成时 have/has done 从句：一般过去时 常回答：How long…? since 讲解（2） 常见结构： 1.since + 过去时间点 since 2018, since last year 2.since + 一般过去时从句 since I was young 例句：She has worked here since she left school. since 拓展易错点 since 后接过去时间 for 后接一段时间 错误：I have lived here since 3 years. 正确：I have lived here for 3 years. 正确：I have lived here since 3 years ago. until 讲解（1） 含义：直到……为止 肯定句用法： 主句动作一直持续到从句动作发生 结构：主语 + 动词（延续） + until … 例句：Wait here until the rain stops. until 讲解（2） 否定句：not … until … 含义：直到……才…… 主句动作直到从句发生才开始 时态：过去/将来均可 例句：He didn’t leave until I came back. until 时态规则 将来时：主将从现 I will wait until you finish. 过去时：主过从过 He didn’t go to bed until she returned. 提示：until 从句不用将来时 三个连词核心对比（表格） 连词 含义 主句时态 从句时态 as soon as 一…就… 将来/过去 现在/过去 since 自从 现在完成时 一般过去时 until 直到 一般时 一般时 做题三步骤（必记） 1.看句意：先后/持续/直到 2.看时态：主将从现、完成时 3.看固定：since+过去；not…until 4.检查：从句不能用 will 易混点对比（1） as soon as：动作紧接 I’ll start as soon as you arrive. since：从过去到现在 I have waited since 2 o’clock. 易混点对比（2） until 肯定：一直做 He worked until midnight. not…until：直到才 He didn’t work until 10 o’clock. 课堂小例句（as soon as） 1.I will write to you as soon as I get there. 2.She smiled as soon as she saw me. 3.As soon as he comes, we will begin. 课堂小例句（since） 1.I have loved music since I was a child. 2.He has been here since 2020. 3.How long have you studied? Since 2019. 课堂小例句（until） 1.Please wait until I return. 2.Don’t open the door until the bus stops. 3.He didn’t understand until I explained. 习题1：单项选择 1.I will tell him ________ he comes back. A. as soon as B. since C. until 2.He has lived here ________ he was 10. A. as soon as B. since C. until 3.She didn’t sleep ________ her mom came. A. as soon as B. since C. until A B C 4.We will start ________ everyone is ready. A. as soon as B. since C. until 5.I have known her ________ 2017. A. as soon as B. since C. until 6.Wait ________ the light turns green. A. as soon as B. since C. until A B C 习题2：用 as soon as / since / until 填空 1.I will call you _____________ I arrive home. 2.He has been a teacher _____________ 2019. 3.Don’t get off _____________ the bus stops. 4.She began to run _____________ she heard the bell. 5.I haven’t met him _____________ last week. as soon as since until as soon as since 习题3：句型转换（合并句子） 1.I will finish my work. I will go shopping. → I will go shopping ________ I finish work. 2.He started learning drawing. He was 5. → He ________ ________ drawing since he was 5. 3.We didn’t begin. The teacher arrived.→ We ________ begin ________ the teacher arrived. 4.Wait here. I come back.→ Wait here ________ I come back. as soon as has learned / has studied didn’t until until 习题4：单句改错（每题一处错） 1.I will go as soon as I will get ready. 2.She has lived here since 5 years. 3.He didn’t come until his mother comes. 4.We will start until everyone comes. will get → get since → for 或 5 years 后加 ago comes → came will start → won’t start 习题5：篇章填空（成长话题） I love my job. I start working 1______________ I get to the museum. I have loved dinosaurs 2________ I was a little child. I will keep working 3________ I finish my task. I have studied them carefully 4________ last year. as soon as since until since 课堂小结1：as soon as 含义：一……就…… 时态：主将从现 / 主过从过 逻辑：动作紧接发生 从句：永远不用 will 例句：I’ll go as soon as I can. 课堂小结2：since 含义：自从……以来 时态：主句现完，从句过去 标志：How long 提问 易错：since+时间点；for+时间段 课堂小结3：until 肯定：动作持续到… 否定：not…until 直到…才… 时态：主将从现 / 主过从过 逻辑：动作终止或开始时间 课堂小结4：总口诀 一…就用 as soon as，主将从现不能忘。 自从以来用 since，主句现完从句过。 直到为止用 until，not…until 直到才。 从句时态要注意，不用将来用现在。 常见错误提醒 1.as soon as 从句不用 will 2.since 不能接一段时间 3.not…until 否定不能少 4.从句永远用陈述语序 5.完成时要搭配 since 教学课件 Unit2 语法专项—— 时间状语从句 Thank you for listening! 30 $