Unit4语法讲解及习题：before _ after _ as 引导的时间状语从句2026-2027学年冀教版英语九年级上册

该初中英语单元知识清单系统梳理了冀教九上Unit4中before/after/as引导的时间状语从句语法内容，涵盖连词定义用法、时态规则、易混辨析三大知识范畴，为学生搭建了从“基础概念理解”到“时态逻辑运用”再到“易混点区分”的递进式学习支架。 清单采用“核心知识点分层讲解”和“专项习题梯度设计”构建知识体系，如将“主将从现”标注为考试高频考点，通过连词填空、句型转换等题型培养学生语言能力和思维品质。特别设计“易混辨析对比”和“实例解析”，如before与after动作顺序对比，不同水平学生可高效掌握，教师可直接用于课堂教学或分层辅导，提升教学针对性。

冀教英语九上Unit4语法讲解及习题： before / after / as 引导的时间状语从句 一、语法核心知识点梳理 本单元语法为由 before, after, as 引导的时间状语从句（Adverbial clauses with before/after/as），用于描述动作发生的先后顺序或是同步发生的过程，从句可以放置在主句之前，也可以放置在主句之后。 （一）三个连词核心定义、用法、例句 1. before 含义：在…… 之前，从句对应的动作发生时间早于主句动作。 存在两种常用句式结构： 1）从句 + 逗号 + 主句（Before + 从句，主句） 2）主句 + before + 从句（主句 before + 从句） 时态要求：主从句时态需要符合逻辑，日常多用一般过去时、一般现在时。 例句：Before Helen got sick, she was a bright and happy girl. 在海伦生病之前，她是一个开朗快乐的女孩。 例句：Before Yuan Longping devoted himself to hybrid rice, he studied agriculture hard. 在袁隆平投身杂交水稻研究之前，他刻苦研习农学。 2. after 含义：在…… 之后，从句动作率先完成，主句的动作在从句动作结束之后才发生。句式结构和 before 完全一致。 例句：After she lost her ability to see and hear, she became difficult and wild. 在丧失视觉和听觉之后，她变得暴躁难以管束。 例句：After Helen received Anne Sullivan’s help, she began to learn words. 在海伦得到安妮・沙利文的帮助之后，她开始学习文字。 3. as 含义：当…… 的时候；随着，侧重两个动作同步开展，伴随整个过程同步进行。 例句：As Helen grew older, she made a lot of progress and learned to read. 随着海伦慢慢长大，她取得巨大进步，学会了阅读。 例句：As Hawking studied in Oxford, he showed great talent in physics. 霍金在牛津求学期间，展现出极高的物理天赋。 （二）通用时态使用规则 1. 过去时态语境 讲述过往事件时，主句、从句统一使用一般过去时，依靠 before、after、as 区分动作先后，时态不作改动。 例：As Marie Curie did experiments, she never gave up. 居里夫人做实验的时候，她从未放弃。 2. 将来时态语境（主将从现，考试高频考点） 如果主句采用一般将来时，before、after、as 引导的从句必须使用一般现在时来表达将来含义。 例：I will write a report about great people after I finish my homework. 我写完作业之后，会写一篇关于伟人的报告。 3. 标点使用细节 从句置于句首，从句末尾必须添加逗号；从句放在主句末尾，不需要使用逗号。 · Before he became famous, he lived a hard life.（有逗号） · He lived a hard life before he became famous.（无逗号） （三）易混辨析 1. before 代表主句动作发生在后，after 代表主句动作发生在前，二者词义互为相反。 2. as 着重体现动作全程同步进行，做题时只要判定两件事在同一个时间段内发生，即可选用 as。 二、专项分层练习题（ 题型一：连词填空 选用 before, after, as 填空，单词可以重复使用。 1. _________Helen understood the word water, she was confused about finger spelling. 2. She learned to speak _________she entered the university. 3. _________time went by, Tu Youyou discovered artemisinin. 4. Hawking became ill _________he finished his study at Oxford University. 5. Wash your hands _________you have meals. 6. We took many photos _________the famous scientist left. 7. _________she read lots of books, Helen decided to help disabled people. 8. The students kept quiet _________the teacher walked into the classroom. 题型二：单项选择题 9. Helen ________ able to write many books after she ________ educated by Anne. A. was; was B. is; was C. was; is 10. I ________ make a poster about great people before I ________ my English class tomorrow. A. will; have B. will; will have C. am; will have 11. As the old scientist ________ his speech, all listeners kept silent carefully. A. gave B. gives C. will give 12. You can’t know the difficulty ________ you experience it yourself. A. after B. before C. as 13. ________ Stephen Hawking got the terrible illness, he loved physics very much. A. Before B. After C. As 14. She cried happily ________ she knew she could go to college. A. as B. before C. after 15. —When did you write the article about Yuan Longping? —I wrote it ________ I watched a documentary about him. A. after B. as C. before 16. ________ we learn the stories of great people, we can learn their good qualities. A. After B. Before C. As 17. Don’t give up ________ you reach your final success. A. after B. before C. as 18. As he ________ growing up, his dream ________ become a physicist came true. A. was; to B. is; will C. was; would 19. I will finish my project ________ my teacher checks my work. A. before B. after C. as 20. Many people knew about Helen Keller ________ her books came out around the world. A. after B. as C. before 题型三：句子仿写填空 参照本单元语法结构，使用 before /after/as 补全句子，答案不唯一。 21. The audience cheered loudly as ________________________________. 22. ______________________________before I began to write about my admired person last night. 23. ______________________________after Tu Youyou won the Nobel Prize. 24. As ________________________________, he formed the idea of saving poor farmers. 25. I had learned basic English ________________________________. 题型四：短文选词填空 备选选项： A. Before he became a high school student B. As he was a student in Oxford University C. after he had a terrible disease D. After three years 阅读短文，将对应字母填入横线。 Stephen Hawking was a famous physicist in the U.K. 26. ________, he was curious about the world around him. In high school, he found his love for maths after he was inspired by his teacher. 27. ________, he spent most of his time studying. 28. ________, he graduated with first-class honours. In 1963, Hawking’s life changed 29. ________. He died in 2018 after a long battle with this disease, ALS. 题型五：句型转换 按照括号内要求改写句子 30. Before Helen got sick, she was bright and happy.（改为同义句，使用 after 改写） 31. As she grew older, Helen learned to read and write.（拆分为两个简单句） 32. I will finish my project. Then I share it with classmates.（合并为含有 before 引导状语从句的复合句） 33. He became well-known. He wrote several great books.（用 after 合并两个句子） 三、参考答案与解析 题型一：连词填空答案 + 解析 1. 答案：Before 解析：海伦弄懂 water 这个单词发生在后，困惑发生在前，选用 before 表示 “在…… 之前”。 2. 答案：after 解析：进入大学在先，学会说话在后，after 指代主句动作发生在从句动作之后。 3. 答案：As 解析：as 此处含义为 “随着”，用来体现时间同步推进的过程。 4. 答案：after 解析：结束牛津的学业之后霍金患上重病，动作存在先后顺序。 5. 答案：before 解析：吃饭之前需要洗手，饭前为动作的前置条件。 6. 答案：before 解析：我们拍照的行为发生在科学家离开之前。 7. 答案：After 解析：读完大量书籍之后，海伦下定决心帮助残障人士。 8. 答案：as 解析：老师走入教室的整个过程中，学生保持安静，两个动作同步发生。 题型二：单项选择题答案 + 解析 9. 答案：A 解析：讲述海伦过往的人生经历，主句和从句统一使用一般过去时。 10. 答案：A 解析：本题考查主将从现，主句使用一般将来时，before 引导的时间从句要用一般现在时表将来。 11. 答案：A 解析：主句时态为一般过去时，as 引导同步发生的过去动作，动词选用过去式 gave。 12. 答案：B 解析：句意：你只有亲身经历过后才能够明白这份艰难，换而言之在经历之前无法体会，before 符合语义。 13. 答案：A 解析：霍金在患上顽疾之前就十分热爱物理学。 14. 答案：C 解析：得知可以进入大学这件事在前，喜极而泣在后，选用 after。 15. 答案：A 解析：观看纪录片的动作在前，撰写文章在后，使用 after。 16. 答案：A 解析：学习伟人的事迹之后，我们可以学习他们宝贵的品质。 17. 答案：B 解析：句意：抵达最终的成功之前，请不要放弃。 18. 答案：A 解析：was growing up 为过去进行时，表达 “随着他渐渐长大”；不定式 to do 可以作后置定语修饰名词 dream。 19. 答案：A 解析：我会在老师检查作业之前完成我的任务，before 满足语境逻辑。 20. 答案：A 解析：海伦的著作在全世界发行之后，越来越多人了解到她的故事。 题型三：句子仿写填空（参考作答，答案不唯一） 21. 参考答案：the famous scientist walked onto the stage 解析：as 引导同步发生的过去动作，描绘科学家走上舞台时观众欢呼的画面。 22. 参考答案：I collected plenty of materials about great people 解析：时间状语 last night 限定整体时态为一般过去时，搜集资料发生在动笔写作之前。 23. 参考答案：More Chinese young people decided to study medicine 解析：屠呦呦斩获诺贝尔奖这件事在前，大批青年立志学医在后。 24. 参考答案：Yuan Longping worked in the countryside 解析：as 体现伴随过程，在袁隆平扎根乡村工作的过程中，萌生帮扶贫苦农民的想法。 25. 参考答案：before I started my ninth-grade English study 解析：主句采用过去完成时，代表动作发生在九年级英语课程开启之前。 题型四：短文选词填空答案 + 解析 26. 答案：A 解析：句意：在成为一名高中生之前，霍金就对周遭的世界充满好奇。 27. 答案：B 解析：as 表示在牛津大学就读的这段时期内，霍金将大部分时间投入学习。 28. 答案：D 解析：承接上文，数年的学业结束之后，他以优异的成绩顺利毕业。 29. 答案：C 解析：1963 年霍金确诊病症，在患上这场重病之后，他的人生轨迹发生巨大改变。 题型五：句型转换参考答案 + 解析 30. 参考答案：After Helen got sick, she was no longer bright and happy. 解析：原句表达海伦患病之前性格开朗，改写之后借助 after 转换逻辑，表达患病之后她不再乐观开朗。 31. 参考答案：Helen grew older. At the same time, she learned to read and write. 解析：as 的核心含义为两件事同步发生，拆分两个简单句，用 at the same time 体现动作并行的关系。 32. 参考答案：I will finish my project before I share it with classmates. 解析：合并之后遵循主将从现规则，主句为一般将来时，从句使用一般现在时。 33. 参考答案：He became well-known after he wrote several great books. 解析：写书的动作率先发生，获得名望发生在后，使用 after 引导时间状语从句。 ( 1 ) 学科网（北京）股份有限公司 $