Unit8语法讲解及习题_原因状语从句（Adverbial clauses of reason） 2025-2026学年沪教版八年级英语下册

沪教（牛津）英语八下Unit8语法讲解及习题 原因状语从句（Adverbial clauses of reason） 一、语法概念 原因状语从句用于说明事情发生的原因，本单元重点学习由 because / as / since 引导的原因状语从句，以及 because of 引导的原因短语，是解释观点、描述故事背景的常用语法。 二、详细用法讲解 1. because / as / since 引导的原因状语从句 含义：三者均可表示“因为”，语气略有不同： because：语气最强，强调直接原因，回答“why”的问句。 as / since：语气较弱，侧重“既然/由于”，常放在句首，引出已知的原因。 结构： 从句可放在主句前或后： 放在句首：As/Since/Because + 从句, 主句（句首从句后需加逗号） 放在句末：主句 + because/as/since + 从句 例句： Because a spaceship crashed in the forest, there was a loud noise. As it was too late to go outside, they decided to go the next day. Since no one else saw the aliens, their father refused to believe them. 2. because of 引导的原因短语 含义：表示“因为/由于”，后接名词、名词短语或代词，不能接句子。 例句： The spaceship couldn’t fly because of the damage. They were late because of the heavy rain. 三、习题训练 （一）用because / as / since / because of填空 1. There was a loud noise ___________ a spaceship crashed in the forest. 2. ___________ it was too late, they decided to go the next day. 3. The spaceship couldn’t fly ___________ the damage. 4. ___________ no one else saw the aliens, their father refused to believe them. 5. Tina was sure something landed ___________ she heard a loud noise. 6. They hid behind bushes ___________ they were afraid. 7. They ran away ___________ an alien made a terrible noise. 8. ___________ the weather was bad, the flight was delayed. 9. The meeting was cancelled ___________ the absence of the manager. 10. ___________ you are interested in space, you should watch this documentary. （二）用所给提示完成句子 1. Tina was sure something landed in the forest ___________ (because / she heard a loud noise). 2. They hid behind bushes ___________ (because of / fear). 3. They ran away ___________ (as / an alien saw them). 4. His father refused to believe him ___________ (since / no one else saw the aliens). 5. The spaceship couldn’t fly ___________ (because of / serious damage). 6. They didn’t go outside ___________ (because / it was too late). 7. ___________ (since / it was getting dark), they decided to return. 8. The forest was quiet ___________ (because of / the late hour). 9. ___________ (as / they were curious), they went to check the noise. 10. They were excited ___________ (because / they found something unusual). （三）选择正确的选项 1. ___________ the spaceship crashed, there was a loud noise. A. Because of B. Because C. Since of 2. They couldn’t go out ___________ the heavy rain. A. because B. as C. because of 3. ___________ no one else saw the aliens, his father didn’t believe him. A. Since B. Because of C. For 4. She was late ___________ she missed the bus. A. because of B. because C. as of 5. The flight was cancelled ___________ the bad weather. A. because B. as C. because of （四）改写句子 1. Because the damage was serious, the spaceship couldn’t fly. → The spaceship couldn’t fly ___________ ___________ the serious damage. 2. Since it was too late, they didn’t go outside. → ___________ ___________ ___________ ___________, they didn’t go outside. 3. They ran away because an alien made a terrible noise. → They ran away ___________ ___________ a terrible noise from the alien. 4. As they were curious, they went to check the forest. → ___________ ___________ ___________, they went to check the forest. 5. Because of the late hour, the forest was quiet. → The forest was quiet ___________ ___________ ___________ ___________. （五）翻译句子 1. 因为一艘宇宙飞船坠毁在森林里，所以有很大的噪音。 _____________________________________________________________________ 2. 由于天色太晚，他们决定第二天再去查看。 _____________________________________________________________________ 3. 宇宙飞船因为损坏而无法飞行。 _____________________________________________________________________ 4. 既然没有其他人看到外星人，他父亲就不相信他。 _____________________________________________________________________ 5. 他们躲在灌木丛后，因为害怕被发现。 _____________________________________________________________________ 四、答案及解析 （一）用because / as / since / because of填空 1. because（强调直接原因，回答why） 2. As/Since（句首，语气较弱，引出已知原因） 3. because of（后接名词the damage） 4. Since/As（句首，侧重“既然”） 5. because（强调直接原因） 6. because/as/since（均可，说明原因） 7. because（强调直接原因） 8. As/Since（句首，引出原因） 9. because of（后接名词absence） 10. Since/As（句首，侧重“既然”） （二）用所给提示完成句子 1. because she heard a loud noise 2. because of fear 3. as an alien saw them 4. since no one else saw the aliens 5. because of serious damage 6. because it was too late 7. Since it was getting dark 8. because of the late hour 9. As they were curious 10. because they found something unusual （三）选择正确的选项 1. B（后接句子，用because） 2. C（后接名词短语，用because of） 3. A（后接句子，用since） 4. B（后接句子，用because） 5. C（后接名词短语，用because of） （四）改写句子 1. because of the serious damage 2. As it was too late 3. because of a terrible noise from the alien 4. Since they were curious 5. because it was late （五）翻译句子 1. There was a loud noise because a spaceship crashed in the forest. 2. As/Since it was too late, they decided to check it the next day. 3. The spaceship couldn’t fly because of the damage. 4. Since no one else saw the aliens, his father refused to believe him. 5. They hid behind bushes because they were afraid of being discovered. ( 1 ) 学科网（北京）股份有限公司 $