大学英语从句.ppt

Thank You! （1）时间状语从句 (adverbial clause of time) ②.while当...时 He visited a lot of places while he was traveling. 他在旅途中参观了许多地方。 ③.as在...的同时；一边...一边... He smiled as he stood up. 他一边站起来一边笑着。 ④.after在...之后 He left the classroom after he had finished his homework the other day. 前几天做完作业之后回的家。 （1）时间状语从句 (adverbial clause of time) ⑤.before 在...之前 Mr. Brown had worked in a bank for a year before he came here. 布朗先生来这之前已经在一家银行里工作一年了。 ⑥.as soon as 一...就... We began to work as soon as we got there. 我们一到那就开始工作。 I will write to you as soon as I get home. 我一到家就给你写信。 （1）时间状语从句 (adverbial clause of time) ⑦.since 自…以来 到现在 表示自过去的一个起点时间到目前(说话时间)为止的 一段持续时间。主句一般用现在完成时，从句用一般 过去时。 Mr Green has taught in that school since he came to China three years ago. 自格林先生来中国以来，他就在这所学校教书。 （1）时间状语从句 (adverbial clause of time) ⑧ till /until 都可以作连词，连接时间状语，也可以 作介词，与其它词构成介词短语，在句中作状语。 They walked till /until it was dark. 他们一直走到天黑。 Xiao Ming didn’t leave home till / until his father came back. 小明直到他爸爸回来才离开家。 ⑨. by the time 到。。。为止 By the time he gets there, his father has already gone. 他到家的时候，他爸爸已经走了。 By the time I got to school, the class had already began. 我到校时，已经开始上课了。 说明： A．由when, while, as引导的时间状语从句。 when引导的从句的谓语动词可以是延续性的动词，又可以 是瞬时动词。并且when有时表示“就在那时”。如： When she came in, I stopped eating.她进来时，我在吃饭。 (瞬时动词) When I lived in the countryside, I used to carry some water for him. 当我住在农村时，我常常为他担水。（延续性的动词） We were about to leave when he came in. 我们就要离开，就在那时他进来了。 说明： A．由when, while, as引导的时间状语从句。 While引导的从句的谓语动作必须是延续性的，并强调主句 和从句的动作同时发生（或者相对应）。并且while有时还 可以表示对比。如： While my wife was reading the newspaper, I was watching TV. 我妻子看报纸的时候我正在看电视。(was reading是延续性 的动词，was reading和was watching同时发生) I like playing football while you like playing basketball. 我喜欢踢足球，而你喜欢打篮球。（对比） 说明： A．由when, while, as引导的时间状语从句。 As表示“一边……一边”，as引导的动作是延续性的动作，一般 用于主句和从句动作同时发生；as也可以强调“一先一后。 例如： We always sing as we walk.我们总是边走边唱。 （as表示“一边……一边”） As we was going out, it began to snow. 当我们出门时，开始下雪了。 （as强调句中两个动作紧接着先后发生，而不强调开始下雪的 特定