Unit 4 语法(before/after/as引导时间状语从句)讲解与练习 2026-2027学年冀教版英语九年级上册

该初中英语导学案围绕Unit4 Great people展开，核心讲解before/after/as引导的时间状语从句，涵盖基础概念、用法、时态规则、句型转换及易错警示。通过单元话题例句连接伟人故事，搭建新旧知识支架，引导学生从已知过渡到语法新知。 资料以“伟人故事”为语境设计例句与练习，融合文化意识，助力学生涵养品格。多样化习题（填空、选择、改写、翻译）分层训练，提升语言能力与思维品质，易错警示强化语法逻辑，便于自主学习，有效培养学习能力。

Unit4 Great people语法讲解与练习 语法讲义：before /after/as引导时间状语从句 一、基础概念 时间状语从句：由连词引导,在复合句中充当时间状语,说明主句动作发生的时间。 本单元重点连词：before, after, as 二、三个连词详细用法 1. before 在……之前 含义：从句动作发生晚于主句动作。 结构：主句+ before +从句= Before +从句,主句.（句首从句后加逗号） ✅ I will make a plan before I start my research. 在我开始研究之前，我会制定一份计划。 ✅ Before he becomes a scientist, he studies hard. 在他成为科学家之前，他努力学习。 2. after 在……之后 含义：从句动作发生早于主句动作。 ✅ He carried out the experiment after he got enough materials. 他拿到充足材料之后开展实验。 ✅ After he received the prize, he gave a short speech. 他获奖之后，发表了简短演说。 3. as 两层核心含义（中考必考） ① 当…… 的时候（=when，强调主从句动作同时发生） As he worked, he thought about the theory. 他一边工作，一边思考这个理论。 ② 随着……（强调伴随变化） As time goes by, more people know about the great pioneer. 随着时间流逝，更多人了解这位伟大先驱。 区分：when:可同时/先后发生； as:侧重同步进行、伴随变化。 三、时态总规则 *将来情景 →主将从现 We will draw a conclusion after we finish the discussion. （主句 will，从句一般现在时 finish） *过去情景（描述伟人往事）→主从句统一使用一般过去时 He continued studying after he suffered difficulties. 他在遭遇困境之后依然坚持研究。 *客观事实、常态 →主从句全部一般现在时 Many scientists think carefully as they do experiments. 四、句型转换常用考点 before /after 可以转换为 after /before +动名词 (doing) He will do research. Before that, he reads many articles. = He will do research before reading many articles. 五、易错警示 ❌ I will tell you the news before I will meet him. ✅ I will tell you the news before I meet him. （从句不能使用 will，主将从现！） ❌ As he will grow older, he understood the theory. ✅ As he grew older, he understood the theory. （描述过去同步动作，统一过去时） 六、单元话题例句 1.He served as a soldier before he became an educator. 2.After Yuan Longping did lots of experiments, he developed hybrid rice. 3.As people learn more about him, they respect this great hero. 4.He extended his research after he received the big prize. 5.Think twice before you draw a conclusion. 【配套专项练习】 一、用所给单词的适当形式填空 1.He ____________ (become) a pioneer after he ____________ (do) years of research. 2.I ___________ (share) the conclusion with you after I _________ (finish) the report tomorrow. 3.Think carefully before you ____________ (reach) a decision. 4.As he ____________ (work), he kept writing new theories. 5.Before the scientist ____________ (receive) the prize, he spent all his time on agriculture. 6.As time ____________ (go) by, more people know this gifted mathematician. 7.She ____________ (operate) on the patient after she ____________ (study) the illness carefully. 8.You ____________ (get) more knowledge as you ____________ (read) more articles. 9.Before they ____________ (sail) on the voyage, they prepared enough food. 10.We ____________ (not make) a plan before we ____________ (talk) with the educator. 11.As the scientist ____________ (extend) his research, he found new sources. 12.After he ____________ (serve) in the army, he began to study science. 13.He ____________ (not draw) a conclusion before all facts ____________ (collect). 14.As you ____________ (travel), you can learn more about different heroes. 15.Before he ____________ (be) famous, he worked tirelessly day and night. 16.The doctor ____________ (start) the operation after he ____________ (check) the patient. 17.As we ____________ (learn) about great people, we can get lots of spirit power. 18.They ____________ (begin) the discussion after the leader ____________ (arrive). 19.Don’t give up before you ____________ (try) your best. 20.As the number of experiments ____________ (grow), he found a new method. 21.After he ____________ (win) the big prize, he kept his modest style. 22.We ____________ (understand) the theory better as we ____________ (read) more essays. 23.Before you ____________ (publish) the article, check every detail. 24.As the sun ____________ (rise), the soldier continued his march. 25.After the scientist ____________ (introduce) the new idea, many people discussed it. 二、单项选择 1.I will tell you the truth ______ we finish our talk. A. before B. after C. as D. until 2.______ he worked, he recorded every small discovery. A. After B. Before C. As D. If 3.You should think twice ______ you make an important decision. A. after B. as C. before D. when 4.As time ______, people remember the great hero forever. A. go by B. goes by C. went by D. will go by 5.He developed hybrid rice ______ he did thousands of experiments. A. before B. after C. as D. while 6.We ______ start the meeting ______ the educator arrives. A. won’t; before B. will; before C. don’t; after D. won’t; after 7.______ he grew older, he understood the value of hard work. A. Before B. After C. As D. Unless 8.You ______ get the conclusion ______ you finish all the surveys. A. will; after B. won’t; after C. will; before D. don’t; before 9.He worked tirelessly ______ he became a famous scientist. A. after B. before C. as D. since 10.As he ______ the experiment, he found something special. A. does B. did C. will do D. is doing 11.Please wait here ______ I come back. A. before B. after C. as D. until 12.He became a soldier ______ he left his hometown. A. as B. before C. after D. when 13.—When will you share the essay? —I ______ send it to you ______ I finish writing. A. will; after B. won’t; after C. will; before D. don’t; before 14.______ you draw a conclusion, check all your information. A. After B. Before C. As D. If 15.As more people ______ about Yuan Longping, they respect him deeply. A. learn B. learns C. learned D. will learn 三、句子改写（使用 before /after/as 合并句子） 1.He finished the research. Then he received the big prize. ______________________________________________________ 2.Think carefully. Then you make a decision.（用 before） ______________________________________________________ 3.He worked. At the same time, he wrote many articles.（用 as） ______________________________________________________ 4.We will have a discussion. We finish reading the essay.（用 after） ______________________________________________________ 5.He became famous. He worked tirelessly for years.（用 before） ______________________________________________________ 6.Time goes by. We know more about this great pioneer.（用 as） ______________________________________________________ 7.Check all the facts. Then you draw a conclusion.（用 before） ______________________________________________________ 8.The doctor checked the patient. Then he started the operation.（用 after） ______________________________________________________ 9.You can understand the theory. You read more materials.（用 after） ______________________________________________________ 10.He joined the army. Then he met the educator.（用 after） ______________________________________________________ 四、汉译英句子翻译 1.在你得出结论之前，请核对所有信息。 _________________________________________________ 2.做完数千次实验之后，他成功培育出杂交水稻。 _________________________________________________ 3.随着时间流逝，人们永远铭记这位伟大的英雄。 _________________________________________________ 4.在成为一名教育家之前，他当过士兵。 _________________________________________________ 5.等我读完这篇文章之后，我会和你分享观点。 _________________________________________________ 6.他一边做实验，一边记录每一个发现。 _________________________________________________ 7.在做出重要决定之前，你必须认真思考。 _________________________________________________ 8.随着我们了解更多伟人的故事，我们能够学到很多东西。 _________________________________________________ 9.收到奖项之后，他依旧坚持研究农业。 _________________________________________________ 10.在你发表短文之前，请仔细检查细节 _________________________________________________ Keys 一、词形填空 1.became; did 2.will share; finish 3.reach 4.worked 5.received 6.goes 7.will operate; study 8.will get; read 9.sailed 10.won’t make; talk 11.extended 12.served 13.won’t draw; are collected 14.travel 15.was 16.will start; checks 17.learn 18.will begin; arrives 19.try 20.grew 21.won 22.will understand; read 23.publish 24.rose 25.introduced 二、单项选择 1.B 2.C 3.C 4.B 5.B 6.A 7.C 8.A 9.B 10.B 11.A 12.C 13.A 14.B 15.A 三、句子改写 1.He received the big prize after he finished the research. 2.Think carefully before you make a decision. 3.As he worked, he wrote many articles. 4.We will have a discussion after we finish reading the essay. 5.He worked tirelessly for years before he became famous. 6.As time goes by, we know more about this great pioneer. 7.Check all the facts before you draw a conclusion. 8.The doctor started the operation after he checked the patient. 9.You can understand the theory after you read more materials. 10.He met the educator after he joined the army. 四、汉译英参考范文 1.Check all the information before you draw a conclusion. 2.After he did thousands of experiments, he developed hybrid rice. 3.As time goes by, people remember the great hero forever. 4.He worked as a soldier before he became an educator. 5.I will share my opinions with you after I finish reading the article. 6.As he did experiments, he recorded every discovery. 7.You must think carefully before you make an important decision. 8.As we learn more stories of great people, we can learn a lot. 9.After he received the prize, he still kept studying agriculture. 10.Please check the details carefully before you publish the essay. 2 / 2 学科网（北京）股份有限公司 $