时间状语从句module3.pptVIP

Grammar Adverbial clause of time When the clock struck twelve, all the lights in the streets were still on. When he was at college, he studied very hard. I will see you when I come back from America. He went home when he had finished his homework. Jane was dressed in blue, while Mary was dressed in red. One person may like to spend his vacation at the seashore, while another may prefer the mountains. when, as, while 总结 1、When可指时间点，又可指时间段，从句中可用延续性动词，也可用非延续性动词。2、While总是指一个时间段，从句中必须用延续性动词。3、as多用于平行结构。表示两个动作同时发生：一个主语同时进行两个动作：一种状态随另一种状态的变化而变化。 区别 when从句的谓语动词可以在主句谓语动作之前或同时发生；while和as从句的谓语动作必须是和主句谓语动作同时发生。  1. 从句动作在主句动作前发生，只用 when。  When he had finished his homework，he took a short rest． 2.It’s cold when it snows.暗示一种规律性，表示“每当” 3.固定搭配中： be doing sth when 正在某事，这时…… The children were playing football in the ground when it began to rain. 孩子们正在操场上踢球，这时开始下雨了。 be about to do sth when 正准备做某事，这时…… I was about to tell her the secret when someone patted me on the shoulder. 我正想告诉她这个秘密，这时有人拍了我的 肩 膀。 从句动作和主句动作同时发生，且从句动作为延续性动词时，when，while，as都可使用。（主短从延三者都可，主延从短只能用when 和as） When ／While ／As we were dancing，a stranger came in． （dance为延续性动词）当我们跳舞 时，一位陌生人走了进来。 It was raining when/as we arrived. (arrive 为短暂性动作) 当主句、从句动作同时进行，从句动作的时间概念淡化，而主要表示主句动作发生的背景或条件时，只能用 as。这时，as常表示“随着……”；“一边……，一边……”之意。 As the time went on，the weather got worse．（as表示“随着……”之意） as soon as 的用法 as soon as连接的时间状语从句中，指未发生的动作，规律是：主句一般将来时，从句用一般现在时代替一般将来时 （主将从现） I will tell him the news as soon as he comes back。 They will be crazy as soon as they hear the news 指紧接着发生的两个短动作，主从句都用一般过去时 1)He took out his English books as soon as he sat down 2) We ate a lot as soon as we got home. * * 表示行为发生的时间，一般由副词，介词短语或相当于副词的词组或短语来充当。 For example: He is leaving for Shanghai I bought a computer The school sports meeting will be held 4. I get up 5. He doesn’t go to school tomorrow. 2 days ago. the day after tomorrow. at 6 o’clock today. every day. 时间状