There_be_句型、简单句讲解专用教材.ppt

表示因果关系的连词及并列句 so, for, because, as, since, therefore… 早晨到了，因为鸟叫了。 It is morning, for the birds are singing. 天色不早了，所以我就回家了。 It was late, so I went home. 我不得不熬夜，因为我有许多作业要做。 I have to stay up late, for I have lots of homework to do. 状语从句 状语从句在主从复合句中修饰主句中的动词、形容词或副词等，状语从句由从属连词引导，与主句连接，位于句首时，常用逗号与主句分开，位于句末时，其前一般不用逗号。状语从句根据其用途可分为时间状语从句、原因状语从句、结果状语从句、条件状语从句、让步状语从句、方式状语从句、目的状语从句等。 时间状语从句 When/while/as，before，after, since, not…until, as soon as 当我妈妈进来的时候， 我正在写作业。 I was doing my homework when my mother came in. 直到爸爸回来他才去睡觉。 He did not go to bed until his father came back. 等他讲话一停，我们就去喝点咖啡。 As soon as he stops talking, let’s get some coffee. 1. while, when, as 这三个连词都可引导时间状语从句，但用法有所不同。 1) 当某事正在进行的时候，又发生了另一件事。While, when, as 都可用来引导表示“背景”的时间状语从句。例如： As/When/While I was walking down the street, I noticed a police car. 2) 当两个长动作同时进行的时候，最常用的是while。例如： While mother was cooking lunch, I was doing my homework. 3) 当两个动作都表示发展变化的情况时，最常用的是as。例如： As children get older, they become more and more interested in things around them. 4) 当两个短动作同时发生时，或表示“一边…一边…”时，最常用as。例如： Just as he caught the fly, he gave a loud cry. She looked behind from time to time as she went. 5) 当从句的动作先于主句的动作时，通常用when。例如： When he finished his work, he took a short rest. 6) 当从句是瞬间动作，主句是延续性动作时，通常用when。例如： When John arrived I was cooking lunch. 2. 当主句是一般将来时态或祈使句，表示将来的意义时，从句用一般现在时，简称“主将从现”。 我一到北京就给你打电话。 I’ll ring you up as soon as I get to Beijing. 3. until/till引导的时间状语从句 ①主句的谓语动词是延续性动词时，主句用肯定形式，表示这一动作或状态一直延续到until/till所表示的时间为止。 我会一直等到你来看我。 I’ll wait for you till you come to see me. ②主句的谓语动词是非延续性动词时，用否定形式表示主句的动作直到until所表示的时间才发生。构成not…until,有时不用not，而用其他如never, nothing等表否定意义的词。 我直到完成作业才去睡觉。 I didn’t go to bed until I finished my homework. Since引导的时间状语从句，表示“自……以来”，主句用一般现在时或现在完成时，从句用一般过去时。结构为：It has been…since+从句/ it is…since+从句 从肇庆学院毕业以后,我就一直在这所学校工作 I have worked in this school since I graduated from Zhaoqing University. 我学英语10年了。 It is 10 years since I began to study English. 主句为一般将来时，从句用一般现在时。 如果明天不下雨，我将去长城。