Unit1语法(时间状语从句)讲解与练习-2026-2027学年沪教四五学制版英语八年级上册

该初中英语导学案聚焦as、when、before、until引导的时间状语从句，通过“核心知识点精讲+专项练习”结构展开。课堂导入从回顾简单句入手，逐步过渡到复合句中的时间状语从句，搭建从基础句型到复杂句式的学习支架，帮助学生建立知识脉络。 资料亮点在于知识点分层清晰，通过“含义+核心用法+例句+易混辨析”系统讲解，搭配多样化练习（单词填空、选择、改写、汉译英）及详细解析，有效提升学生语言理解与表达能力，培养分析对比的思维品质，助力自主学习能力发展。

Unit1Water语法讲解与练习 as/when/before/until引导的时间状语从句讲解 一、核心知识点精讲 时间状语从句在句中作状语，修饰主句的动词、形容词或副词，由 as / when / before / until 引导，遵循主将从现、主过从过核心时态规则： *主句为将来时/祈使句/含情态动词，从句用一般现在时表将来； *主句为过去时，从句多用过去相关时态。 A. when 引导时间状语从句 含义：当……时候（适用范围最广） 核心用法： 可指时间点（瞬间动作），也可指时间段（延续动作）； 可连接短暂性动词（arrive, stop, see）和延续性动词（work, stay, study）； 可表示“突然”，常用于 be doing...when...（正在做……突然……）句型。 1. When I got home, my mother was cooking.（我到家时，妈妈正在做饭。） 2. We were walking in the street when it began to rain. （我们正在街上走,突然下起了雨。） 3. When spring comes, all kinds of flowers bloom. （当春天来临，各种各样的花儿竞相绽放。） B. as 引导时间状语从句 含义：当……时候；一边……一边……；随着…… 核心用法： 侧重两个动作同步进行，强调伴随状态； 多用于延续性动作，不单独指瞬间时间点； 可表示“随着时间推移”，体现渐进过程。 1. As he grew older, he became wiser.（随着年龄增长，他变得更睿智了。） 2. She sang softly as she did her housework.（她一边做家务，一边轻声唱歌。） 3. As time goes by, we forget many unimportant things. （随着时间流逝，我们会淡忘很多无关紧要的事。） C. before 引导时间状语从句 含义：在……之前；没过多久就…… 核心用法： 主句动作发生在从句动作之前； 常用固定句型： It will be +时间段 + before...（再过多久才……）； It was + 时间段 + before...（没过多久就……） 1. Finish your homework before you watch TV.（看电视前先写完作业。） 2. It will be half a year before we meet again.（再过半年我们才能再次见面。） 3. He had left before I arrived at the classroom.（我到教室之前，他就已经离开了。） D. until / till 引导时间状语从句 含义：直到……为止（till 口语化，until 可用于句首、句中） 核心用法： 肯定句：主句动词为延续性动词，表示动作持续到从句动作发生为止； 否定句（not...until）：最常用，意为“直到……才……”，主句动词可为短暂性动词；遵循主将从现，不可与瞬间终止的语境矛盾。 1. I will wait until you come back.（我会一直等，直到你回来。） 2. He didn’t go to bed until his father returned.（他直到爸爸回来才睡觉。） 3. We won’t stop practicing until we get perfect results. （我们不会停止练习，直到取得完美的成绩。） 易混辨析 1. 同步伴随用 as，通用时间用 when； 2. 动作在前用 before，动作截止用until； 3. not...until 为必考固定结构，不可替换为before 二、专项练习题 大题一：单词正确形式填空 根据句意和时态规则，用括号内单词的适当形式填空，一空一词。 1. When I ________ (walk) in the park yesterday, I met an old friend. 2. As the sun ________ (rise), the fog will disappear slowly. 3. You must wash your hands before you ________ (eat) meals. 4. He ________ (not leave) until you promise to help him. 5. When the bell ________ (ring), all the students rushed into the classroom. 6. As she ________ (read) the book, she noted down many useful sentences. 7. It will be two weeks before he ________ (come) back from Beijing. 8. I ________ (wait) here until your teacher arrives. 9. When you ________ (grow) up, you will understand your parents’ love. 10. As time ________ (go) by, we become more mature. 11. He didn’t stop working until he ________ (finish) all the tasks. 12. Before the train ________ (start), we need to get on board. 13. When I ________ (be) young, I liked playing basketball very much. 14. As they ________ (talk), they walked along the river happily. 15. She ________ (not go) out until the rain stops. 16. It was midnight before he ________ (get) home last night. 17. When the teacher ________ (ask) questions, please listen carefully. 18. We will keep learning until we ________ (master) the knowledge. 19. As the wind ________ (blow) strongly, the leaves fell down. 20. Think twice before you ________ (make) a decision. 大题二：单项选择 1. ______ I was watching TV, my sister was doing her homework. A. When B. As C. Before D. Until 2. He didn’t know the truth ______ his friend told him. A. when B. as C. before D. until 3. It will be three days ______ the project is finished. A. when B. as C. before D. until 4. ______ he grew older, he realized the importance of health. A. When B. As C. Before D. Until 5. I will stay here ______ you come back safely. A. when B. as C. before D. until 6. ______ I arrived at the station, the train had already left. A. When B. As C. Before D. Until 7. You should practice more ______ you take the final exam. A. when B. as C. before D. until 8. She sang a song ______ she was cleaning the room. A. while B. as C. before D. until 9. We ______ start the meeting until everyone is present. A. will B. won’t C. did D. didn’t 10. ______ the weather gets warm, the flowers will bloom one by one. A. When B. As C. Before D. Until 11. He rushed out ______ I could say a word. A. when B. as C. before D. until 12. The kids kept playing ______ it was dark outside. A. when B. as C. before D. until 13. ______ I was walking home, it began to rain heavily. A. When B. As C. Before D. Until 14. It was not long ______ he adapted to the new school life. A. when B. as C. before D. until 15. People’s life becomes better ______ society develops. A. when B. as C. before D. until 大题三：句子改写 1. He went to bed after he finished his homework.（用 before 改写） He ______ ______ to bed ______ he finished his homework. 2. I will leave when you come back.（用 not...until 改写） I ______ leave ______ you come back. 3. When he was young, he learned to play the piano.（用 as 改写） ______ he ______ ______, he learned to play the piano. 4. The rain stopped, then we went out.（用 before 改写） We ______ ______ out ______ the rain stopped. 5. She will start working after she gets the notice.（用 not...until 改写） She ______ start working ______ she gets the notice. 6. While my mother was cooking, I was reading.（用 as 改写） I was reading ______ my mother ______. 7. He continued studying till midnight.（用 until 改写） He ______ ______ until midnight. 8. After you understand the rules, you can play the game.（用 before 改写） You ______ play the game ______ you understand the rules. 9. We became friends as time went by.（用 when 改写） We became friends ______ time ______ by. 10. I won’t give up. I achieve my dream.（用 until 合并句子） I ______ ______ up ______ I achieve my dream. 大题四：汉译英翻译 1. 随着科技的发展，我们的生活越来越便利。（as） _____________________________________________________ 2. 直到你道歉，我才会原谅你。（not...until） _____________________________________________________ 3. 在你做任何决定之前，请认真思考。（before） _____________________________________________________ 4. 当我正在跑步的时候，我看到了一只可爱的小狗。（when） _____________________________________________________ 5. 他一直坚持练习，直到他成功为止。（until） _____________________________________________________ 6. 没过多久，他就适应了新的工作环境。（before） _____________________________________________________ 7. 随着年龄的增长，我们会懂得更多道理。（as） _____________________________________________________ 8. 直到天黑，孩子们才结束玩耍。（not...until） _____________________________________________________ 9. 你必须完成作业之后才能看动画片。（before） _____________________________________________________ 10. 当老师走进教室时，同学们都安静了下来。（when） _____________________________________________________ Keys 大题一：单词正确形式填空 1. was walking 解析：when引导过去进行时场景，昨天正在散步时遇见朋友。 2. rises 解析：主将从现，从句一般现在时表将来。 3. eat 解析：before引导从句，主句为祈使句，从句用一般现在时。 4. won’t leave 解析：not...until结构，主将从现。 5. rang 解析：主过从过，主句rushed为过去式，从句用一般过去时。 6. was reading 解析：as强调同步进行，过去正在读书时记笔记。 7. comes 解析：It will be...before...句型，从句用一般现在时。 8. will wait 解析：主将从现，从句一般现在时，主句用将来时。 9. grow 解析：主将从现，when引导时间从句用一般现在时。 10. goes 解析：客观真理、常态现象，一般现在时，time为单数。 11. finished 解析：主过从过，主句didn’t stop为过去式。 12. starts 解析：before引导从句，主句为一般现在时，从句同步。 13. was 解析：when引导过去时间段，小时候的状态，一般过去时。 14. were talking 解析：as强调边走边聊，过去同步进行的动作。 15. won’t go 解析：not...until主将从现结构。 16. got 解析：It was...before...句型，主过从过。 17. asks 解析：主句为祈使句，从句一般现在时，teacher为单数。 18. master 解析：主将从现，从句用一般现在时。 19. blew 解析：主过从过，落叶为过去动作。 20. make 解析：祈使句+before从句，从句一般现在时。 大题二：单项选择 1-5BDCBD 6-10ACBBA 11-15CDACB 大题三：句子改写 1. didn’t go; before 2. won’t; until 3. As; grew older 4. didn’t go; before 5. won’t; until 6. as; was cooking 7. studied on / kept studying 8. can’t; before 9. when; went 10. won’t give; until 大题四：汉译英翻译 1.As technology develops, our lives become more and more convenient. 2.I won’t forgive you until you say sorry to me. 3.Please think carefully before you make any decisions. 4.When I was running, I saw a lovely little dog. 5.He kept practicing until he succeeded. 6.It was not long before he adapted to the new working environment. 7.As we grow older, we will understand more truths. 8.The children didn’t stop playing until it was dark. 9.You can’t watch cartoons before you finish your homework. 10.When the teacher walked into the classroom, all the students became quiet. 2 / 2 学科网（北京）股份有限公司 $