Unit1语法(条件;原因状语从句)讲解与练习-2026-2027学年外研版英语九年级上册

该初中英语导学案聚焦条件状语从句（if/unless）和原因状语从句（because/since/as），通过辨析if的两种身份、unless与if…not转换等方式导入，结合综合对比表梳理语法规则，搭建前后知识衔接的学习支架，帮助学生系统掌握从句用法。 资料亮点在于高频错题汇总精准突破易错点，配套练习题型多样且结合木偶戏等语境，能提升学生语言能力（语法理解与表达）、思维品质（分析对比）和学习能力（自主纠错），助力高效掌握语法，便于教师教学评估与学生自主学习。

Unit1 Teenagers today语法讲解与练习 条件状语从句、原因状语从句详细讲解 第一部分 条件状语从句 一、基本概念 在复合句中,由连词引导的从句用来表示主句动作发生的条件,这个从句就是条件状语从句。 本单元重点连词：if（如果）、unless（除非；如果不） 二、核心语法规则：主将从现（重中之重） 含义：主句描述将来的情况，条件从句要用一般现在时代替一般将来时 细分三种句型结构： A.主句一般将来时（will /won’t +动词原形）+ if 从句（一般现在时）【最常用】 结构 1：If +主语+现一般，主语+ will do…（从句置于句首，中间加逗号） If I have free time, I will watch puppet shows. 如果我有空，我会去看木偶戏。 结构 2：主语 + will do… + if +主语+现一般（从句在后，不加逗号） I will watch puppet shows if I have free time. ⚠️ 易错红线：if 引导条件状语从句，从句中绝对不能使用 will ❌ If I will have time, I will go. ✅ If I have time, I will go. B.主句含有情态动词（can /may/must /should）→主情从现 If you practise hard, you can learn puppetry well. 如果你刻苦练习，你能学好木偶戏。 C.主句为祈使句（表建议、命令、请求）→ 主祈从现 Ask for help if you meet problems. 如果你遇到困难就寻求帮助。 三、连词 unless 深度讲解 unless = if … not 除非，如果不 时态同样遵守主将从现 例句： You won’t enjoy the show unless you understand the story. = You won’t enjoy the show if you don’t understand the story. 除非你看懂剧情，不然你不会喜欢这场演出。 ✅ 句型转换高频考点：unless ↔ if…not 互换 四、易混难点：if 的两种身份（极易丢分） if = 如果 →条件状语从句 →主将从现 If it rains tomorrow, we will stay indoors. if = 是否 →宾语从句 →时态正常，不受主将从现限制 I don’t know if it will rain tomorrow. 我不知道明天是否会下雨。 判断小技巧：if 翻译为如果→条件状语；翻译是否→宾语从句 第二部分 原因状语从句 一、基本概念 从句用来说明主句动作发生的原因、理由，叫作原因状语从句。 重点连词：because, since, as 课文原句： I felt less close to the art because people thought puppets were too old-fashioned. 人们觉得木偶太过老旧，这让我渐渐疏远了这项艺术 二、because 详细用法 含义：因为，语气最强，侧重直接、客观、真正原因 ✅ 专门用来回答 Why 引导的特殊疑问句 —Why do you like puppets? —Because they look lively. 必考禁忌：because 和 so 不能同时出现在一个句子！ 中文习惯 “因为…… 所以……”，英语二者二选一 ❌ Because people dislike puppets, so I feel upset. ✅ Because people dislike puppets, I feel upset. ✅ People dislike puppets, so I feel upset. 时态规则：没有主将从现！ 原因状语从句时态根据事实语境自由选择，前后时态保持逻辑一致 He missed the show because he was ill.（一般过去时） He stays at home because he hates noisy places.（一般现在时） 三、because /since/as 完整辨析 连词 语气 核心用法 位置特点 例句 because 最强 直接根本原因；可回答 why 提问 可前可后 He cried because he lost his puppet. since 中等 既然；显而易见、双方都知道的理由 常放句首 Since you know the truth, I won’t hide it. as 最弱 由于；附带说明原因，多用于口语 多放句首 As it is late, we have to leave. 语气排序：because > since > as 四、句式语序 从句前置：Because/Since/As +从句，主句（必须加逗号） Because puppets are traditional art, we should protect them. 从句后置：主句 + because + 从句（不加逗号） We should protect puppets because they are traditional art. 补充知识点：because of 区分（完形常考） because +完整句子（主谓结构） He gave up because he was tired. because of + 名词/名词短语/动名词（不能加句子） ✅He gave up because of tiredness. ❌ He gave up because of he was tired （错误） 第三部分 两大从句综合对比梳理 项目 条件状语从句（if/unless） 原因状语从句（because/since/as） 连词 if 如果；unless 除非 because 因为；since 既然；as 由于 核心含义 满足某个条件，才会发生某事 解释事情发生的缘由 时态规则 主将从现/主情从现/主祈从现 无时态特殊规则，时态按需匹配 标志性考点 if词义辨析;unless=if…not转换 because 不与so连用；because of区分 第四部分 高频错题汇总 条件状语从句易错点 1.If 从句表示将来条件，从句禁止 will 2.unless 本身带有否定含义，不要再额外加 not ❌ You won’t pass unless you don’t work hard. ✅ You won’t pass unless you work hard. 原因状语从句易错点 1.because 与 so 不能连用 2.区分because +句子; because of +名词短语 3.since 有两个意思：自从（时间状语从句）/既然（原因状语从句） Since he came here, he has loved puppets.（自从,时间从句） Since you are busy, I will go alone.（既然,原因从句） 【配套练习】 一、用所给单词的正确形式填空 规则：重点考查条件状语从句主将从现、时态一致、原因状语从句时态适配 1. If you ________ (practise) puppet shows every day, you will be good at them. 2. We ________ (not go) to the art museum if it rains tomorrow. 3. You can improve your skills if you ________ (be) patient enough. 4. ________ (not give) up if you meet difficulties in your study. 5. Unless he ________ (finish) his homework, he can’t watch the show. 6. I will tell you the truth if you ________ (keep) it a secret. 7. If they ________ (invite) me, I will take part in the performance. 8. The boy feels sad because he ________ (lose) his favourite puppet yesterday. 9. Since you ________ (know) the rule, I won’t explain it again. 10. He doesn’t like old-fashioned art because he ________ (prefer) modern things. 11. If I ________ (have) free time this weekend, I will visit the art exhibition. 12. You ________ (fail) the exam unless you work hard from now on. 13. As it ________ (be) rainy today, we have to stay at home. 14. She ________ (become) more confident if she practises more. 15. Many teenagers dislike traditional puppets because they ________ (think) they are out of date. 16. If the teacher ________ (agree), we will hold a puppet show at school. 17. We can’t go out unless the wind ________ (stop) blowing. 18. He ________ (not join) the club because he has no enough time. 19. Since everyone ________ (be) here, let’s start our class. 20. If you keep trying, you ________ (succeed) one day. 二、单项选择 1. You will miss the school show ________ you hurry up. A. if B. unless C. because D. so 2. He didn’t take part in the activity ________ he was ill. A. so B. because C. because of D. though 3. —Will you go to the art fair tomorrow? —Yes, I will ________ it doesn’t rain heavily. A. if B. unless C. because D. since 4. ________ you are tired, you’d better have a rest. A. Because of B. Since C. So D. But 5. If he ________ hard, he will get good grades in the coming test. A. study B. studies C. will study D. studied 6. I don’t know ________ he will come to watch the puppet show tonight. A. if B. because C. so D. though 7. We should protect traditional art ________ it is part of our culture. A. so B. because C. unless D. if 8. ________ it is late, we still need to finish our homework. A. Because B. Since C. As D. Unless 9. You can’t watch TV ________ you finish your homework first. A. if B. unless C. because D. so 10. He gave up learning puppetry ________ his busy school life. A. because B. so C. because of D. since 三、句型改写 1. If you don’t help me, I can’t finish the work.（改为同义句） I can’t finish the work ________ you help me. 2. He didn’t go to school because he had a cold.（对划线部分提问） ________ ________ he go to school? 3. Work hard, and you will pass the exam.（改为条件状语从句） ________ you work hard, you ________ pass the exam. 4. Because the weather was bad, we stayed at home.（改为简单句） We stayed at home ________ ________ the bad weather. 5. Unless you practise more, you won’t improve.（改为if引导的从句） ________ you ________ practise more, you won’t improve. 6. I will go to the show if I am free.（改为否定句） I ________ ________ to the show if I am not free. 7. Since you are young, you should learn more skills.（改为同义句） You should learn more skills ________ you are young. 8. He likes puppetry because it is a traditional art.（改为简单句） He likes puppetry ________ ________ its tradition. 9. Hurry up, or you will be late.（改为条件状语从句） ________ you ________ hurry up, you will be late. 10. Because he is lazy, he always fails.（去掉because，改写句子） He is lazy, ________ he always fails. 四、汉译英翻译 1. 如果你坚持练习，你的木偶戏会演得越来越好。 _________________________________________________ 2. 除非你亲自体验，否则你不会感受到传统艺术的魅力。 _________________________________________________ 3. 因为木偶戏过时了，现在很少青少年喜欢它。 _________________________________________________ 4. 既然大家都准备好了，我们就开始表演吧。 _________________________________________________ 5. 如果明天天气好，我们就去参观艺术博物馆。 _________________________________________________ 6. 他放弃了学习木偶，因为他没有足够的耐心。 _________________________________________________ 7. 如果你遇到困难，你可以向老师求助。 _________________________________________________ 8. 除非我们努力传承，否则传统艺术会慢慢消失。 _________________________________________________ 9. 由于他很喜欢传统文化，他经常观看木偶表演。 _________________________________________________ 10. 如果你足够自信，你会在舞台上表现得很好。 Keys （一）单词正确形式填空 答案+解析 1. practise 解析：if引导条件状语从句，主将从现，从句用一般现在时。 2. won’t go 解析：主将从现，从句一般现在时，主句用一般将来时否定形式。 3. are 解析：主情从现，主句含情态动词can，从句一般现在时。 4. Don’t give 解析：主祈从现，主句为否定祈使句，结构Don’t+动词原形。 5. finishes 解析：unless引导条件状语从句,主将从现，主语he为三单，动词变形。 6. keep 解析：主将从现，从句主语you，动词用原形。 7. invite 解析：主将从现，从句主语they，动词用原形。 8. lost 解析：because原因状语从句，yesterday为过去时间，用一般过去时。 9. know 解析：since表“既然”，从句陈述客观事实，用一般现在时。 10. prefers 解析：原因状语从句，主语he三单，一般现在时表常态。 11. have 解析：主将从现，从句一般现在时。 12. will fail 解析：unless引导条件句，主将从现，主句将来时。 13. is 解析：as表“由于”，陈述当下事实，一般现在时。 14. will become 解析：主将从现，主句用一般将来时。 15. think 解析：原因状语从句，主语they，一般现在时表普遍看法。 16. agrees 解析：主将从现，主语teacher三单，动词变形。 17. stops 解析：unless条件句，主将从现，主语wind三单。 18. doesn’t join 解析：原因状语从句，表常态，一般现在时否定。 19. is 解析：since表“既然”，当下状态，一般现在时。 20. will succeed 解析：主将从现，主句一般将来时。 （二）单项选择 答案+解析 1. B 解析：unless=if…not，句意：除非你快点，否则你会错过校园演出。 2. B 解析：because后接完整句子表原因；because of后接名词短语。 3. A 解析：if表“如果”，句意：如果不下大雨，我就去艺术展。 4. B 解析：since表“既然”，引导原因状语从句，放句首。 5. B 解析：主将从现，if从句用一般现在时，主语he三单。 6. A 解析：此处if表“是否”，引导宾语从句，非条件句。 7. B 解析：because引导原因状语从句，解释保护传统艺术的原因。 8. C 解析：as表“由于”，侧重附带说明原因，语气最弱。 9. B 解析：unless除非，句意：除非你写完作业，否则不能看电视。 10. C 解析：空后为名词短语，用because of，不用because。 （三）句型改写 答案+解析 1. unless 解析：if…not=unless 2. Why didn’t 解析：对because原因提问用why，过去时助动词用didn’t。 3. If; will 解析：祈使句变条件状语从句，遵循主将从现。 4. because of 解析：because+句子，because of+名词短语，转换简单句。 5. If; don’t 解析：unless=if…not，固定句型转换。 6. won’t go 解析：主将从现，主句将来时否定形式。 7. because 解析：since（既然）与because可互换，表原因。 8. because of 解析：空后为名词，用because of转换简单句。 9. If; don’t 解析：祈使句or句型，可转换为if否定条件句。 10. so 解析：because和so二选一，去掉because用so连接结果。 （四）汉译英 参考答案 1. If you keep practising, your puppet show will be better and better. 2. You won’t feel the charm of traditional art unless you experience it in person. 3. Few teenagers like puppet shows now because they are old-fashioned. 4. Since everyone is ready, let’s start the performance. 5. We will visit the art museum if the weather is fine tomorrow. 6. He gave up learning puppetry because he didn’t have enough patience. 7. If you meet difficulties, you can ask teachers for help. 8. Traditional art will gradually disappear unless we try our best to pass it down. 9. As he likes traditional culture very much, he often watches puppet shows. 10. If you are confident enough, you will perform well on the stage. 2 / 2 学科网（北京）股份有限公司 $