1、状语从句主要用来修饰主句或主句的谓语。状语从句主要用来修饰主句或主句的谓语。状语从句状语从句时间状语从句时间状语从句地点状语从句地点状语从句原因状语从句原因状语从句目的状语从句目的状语从句结果状语从句结果状语从句条件状语从句条件状语从句让步状语从句让步状语从句比较和方式状语从句比较和方式状语从句Why was the teacher angry?Because the girl was late for class.The teacher was angry because the girl was late for class.原因状语从句原因状语从句主句主句引导原因状语从句的从属连词主要的
2、引导原因状语从句的从属连词主要的有有because,as,since。原因状语从句是用来说明引起原因状语从句是用来说明引起主句这个结果的原因的从句主句这个结果的原因的从句。指出句子的主句和原因状语从句。指出句子的主句和原因状语从句。I refuse to believe you because no one else saw these aliens.I refuse to believe you as no one else saw these aliens.I refuse to believe you since no one else saw these aliens.主句主句原因状语
3、从句原因状语从句BecauseAsSinceno one else saw these aliens,I refuse to believe you.观察一下句子，你们能得出什么结论？观察一下句子，你们能得出什么结论？结论：结论：当我们把从句放在句子开头时，当我们把从句放在句子开头时，经常用逗号把从句和主句隔开。经常用逗号把从句和主句隔开。知识拓展知识拓展because,since,as 辨析辨析 because语势最强，用来表示说话人以为听话语势最强，用来表示说话人以为听话人不知道的原因，回答人不知道的原因，回答why提出的问题。当原提出的问题。当原因是显而易见的或已为人们所知，就用因是显而
4、易见的或已为人们所知，就用as或或 since。I didnt go because I was afraid.因为我害怕所以我没有去。因为我害怕所以我没有去。例句例句Since/As the weather is too bad,we have to put off our journey.由于天气太差，我们不得不推迟我们的旅行。由于天气太差，我们不得不推迟我们的旅行。Wed better hurry _ it is getting dark.A.and B.but C.as D.unless 解析：句意：我们最好快点，因为天快黑了。解析：句意：我们最好快点，因为天快黑了。A.and并且；并
5、且；B.but但是；但是；C.as由于，因为；由于，因为；D.unless除非。结合句意，故选除非。结合句意，故选C。C-He was late again today.Do you know why?-_ he stayed up watching football match too late last night.A.Since B.As C.Because D.AndC解析：解析：because用来回答用来回答why的提问，表示直接的提问，表示直接的原因。根据上句的提问的原因。根据上句的提问“Do you know why”,故选故选C。Police officers question
6、s1.Why was Tina sure that something landed in the forest near the hills?2.Why did you and Tina hide behind some bushes?3.Why did you run away?4.Why did your father refuse to believe you?Match the questions with the answers.A.We heard some voices speaking a strange language.B.She heard a loud noise l
7、ast night.C.No one else saw these aliens.D.An alien saw us and made a terrible noise.Toms answers.Answer:1.B 2.D 3.A 4.C Tina was sure that something landed in the forest near the hills because she heard a loud noise last night.Use the questions and answers to complete the police officers notes with
8、 as,since or because.Tom and Tina hide behind some bushes as An alien saw them and made a terrible noise.1.because2.asTom run away because they heard some voices speaking a strange language.3.because4.sinceToms father refuse to believe him since no one else saw these aliens.Find out the rules.Im unh
9、appy because of your marks in the exam.They went to the forest because of their curiosity.Tina woke up at midnight because of a loud noise.She decided to explore the forest because of it.Because of 后可以加名词或者名词短语后可以加名词或者名词短语或者人称代词的宾格形式。或者人称代词的宾格形式。Rules:because引导的原因状语从句，而引导的原因状语从句，而because of 后加名词后加名词
10、或者代词，或者名词短语。或者代词，或者名词短语。because从句与从句与 because of短语可以相互转换。短语可以相互转换。because 和和 because of He cant come because he is ill.He cant come because of his illness.他因病不能来。他因病不能来。because 和和so在汉语中在汉语中因为因为所以所以一般情况是连用的，一般情况是连用的，但是英语中但是英语中because 和和so一般不能连用。一般不能连用。因为下雨，所以我们呆在家里。因为下雨，所以我们呆在家里。正：正：Because it was ra
11、ining,we stayed at home.It was raining so we stayed at home.误：误：Because it was raining,so we stayed at home.练习巩固练习巩固句子改错（画出句子中的错误部分，并改正）句子改错（画出句子中的错误部分，并改正）1.Because he got up late this morning so he missed the early bus.2.He is very happy because his good marks in the exam.去掉去掉because改为改为because of
12、直击中考直击中考【2014.深圳深圳】Why didnt you go to school yesterday?_my mother was in hospital and I had to take care of her.A.Then B.BecauseC.If B试题分析：试题分析：Then那么，然后；那么，然后；Because因为；因为；If是是否，如果。句意：昨天你为什么没有去上学？否，如果。句意：昨天你为什么没有去上学？因为我的母亲生病住院了，我不得不照顾她。结合因为我的母亲生病住院了，我不得不照顾她。结合语境可知选语境可知选B。直击中考直击中考【2011.扬州扬州】He had
13、to retire(退休退休)early poor health.A.as a result B.because B.C.so D.because of试题分析：试题分析：as a result因此，结果是；因此，结果是；because因为，因为，接从句；接从句；so因此；因此；because of因为，接名词性短语。因为，接名词性短语。句意：因为身体不适，他不得不提前退休。结合语句意：因为身体不适，他不得不提前退休。结合语境可知选境可知选D。D直击中考直击中考【2013.苏州苏州】Kelly Clarkson is so popular among young people _ her be
14、autiful voice.A.because B.because of C.instead D.instead ofB试题分析试题分析:句意：凯力句意：凯力.克拉克森因其动听的歌喉克拉克森因其动听的歌喉而深受年轻人喜爱。而深受年轻人喜爱。because因为（后接从句），因为（后接从句），because of 因为（后接短语），因为（后接短语），instead 反而，反而，instead of而不是而不是。根据语境可知其深受年。根据语境可知其深受年轻人欢迎是因为其动听的歌喉，轻人欢迎是因为其动听的歌喉，故选故选B.直击中考直击中考【2012.杭州杭州】-Did you call Sara back?-I didnt need to,_ well have a meeting together tonight.A.though B.unless C.because D.ifC试题分析：试题分析：Though虽然，尽管；虽然，尽管；unless除非；除非；because因为；因为；if是否，如果。句意：是否，如果。句意：-你喊萨拉回你喊萨拉回来了吗？来了吗？我不必。因为我们今晚一起有个会议。我不必。因为我们今晚一起有个会议。故选故选C。Write sentences about the story on page 99 by Using because of.
