Unit 5 Art World 课时 3 Grammar-【帮课堂】2021-2022学年九年级英语上册同步精品讲义（牛津译林版）

Unit 5 Art World Grammar 知识点01 because, since, as 引导的原因状语从句 教材P70-71 【用法详解】 1.原因状语从句通常由because, since, as引导。 He didn’t come to school because he was ill. As it is raining, we shall not go the zoo. Since you can’t answer the question, I’ll ask someone else. 2.because表示直接原因，语气最强。because引导的原因状语从句多放在主句之后。回答由why提出的问题，只能用because。as和since语气较弱，一般用来表示明显的原因。由as和since引导的原因状语从句多放在句首。 ------Why aren’t you going there? ------Because I don’t want to. As he has no car, he can’t get there easily. Since we have no money, we can’t buy it. 3.because和so不能同用在一个句子里。 4.because与because of 的区别: because后只能接句子，而because of 后面只能接名词或名词短语，不能跟句子。 Because of the bad weather, we put off the sports meeting. Because it rained yesterday, we put off the sports meeting. 【典例讲解】 1.Wolves will _________ their lives _________ the loss of the trees and forests. A.lose; because B.lose; because of C.lost; because D.lost; because of 【答案】B 【解析】 句意： 因为许多树和森林的消失，狼将失去生命。lose one’s life失去生命；because后跟句子，空格后没有谓语动词，故排除A、C；will+动词原形，故