2022年九年级中考英语语法知识梳理 - 时间状语从句教案

2022年九年级中考英语语法知识梳理时间状语从句在句中相当于时间状语的从句叫时间状语从句。时间状语从句常由从属连词when，while，as，before，after，as soon as，since，till，until等引导。如：What are you going to be when you grow up ？你长大以后打算干什么？I will phone you as soon as I get there .我一到那儿就给你打电话。1.引导时间状语从句的从属连词及用法（1）when，while，as引导时间状语从句意为“当……时”。如：When the clock struck twelve ，all the lights went out.当时钟敲了十二下，灯全部都熄了。While Peter was reading ，his wife was cooking.彼得看书的时候，他妻子在做饭。He dropped the glass as he stood up .他站起来时，把杯子摔碎了。注意：①when表示“当……时”，多用来表示时间点，也可表示时间段；从句中既可以用非延续性动词，也可用延续性动词；when 从句多用一般过去时，主句时态没有限制，根据具体情况而定；在将来时态中，常用when引导从句，且从句须用一般现在时代替将来时；when表示时间段时可与while通用，但从句中必须用延续性动词。如：I was just reading a book when she came into my room.她走进我房间时，我正在看书。When I got to the airport，the guests had left.当我赶到飞机场时，客人们已经离开了。When the manager comes here for a visit next week，I'll talk with him about this.下周经理来这参观时，我会和他谈谈此事。②while表示“当……的时候；在……之时；在……期间”，所引导的时间状语从句的谓语动词必须是延续性动词或表示状态的动词，且通常用进行时。如：While my wife was reading the newspaper，I was watching TV.当妻子在看报纸的时候，我在看电视。You can't do your homework while you're watching TV.你不能一边看电视一边做家庭作业。③as引导时间状语从句时，从句的谓语动词既可以是延续性的，也可以是非延续性的。当从句中的谓语动词是延续性动词，表示“当……的时候”时，往往可以与when或while通用，但as更侧重主句与从句的行为同时发生，常译作“随着……；一边……，一边……”。如：Kate read the book as she went along.凯特边走边读书。We took notes as we listened to the lecture.我们边听课边记笔记。（2）before引导时间状语从句意为“在……之前”。如：Don't jump off the train before it stops.火车停之前不要往下跳。Look at both ways before you cross the road.过马路之前左右两边都要看。I didn't know any English before I came here。我来这儿之前，一点英语都不懂。（3）after引导时间状语从句意为“在……之后”。如：I'll have a walk after I finish my work.我做完事后要去散步。After he locked the door，he left.他锁上门之后就走了。注意：为了表明动作的先后，从句中动词可用过去完成时，主句用一般过去时。如：After he had finished his work，he played a game of chess with his friends.他做完工作后，和朋友下了一会儿棋。（4）until，till引导时间状语从句意为“直到……为止”。如：They waited till/until I returned.他们一直等到我回来。Mr.Wang kept on explaining until the student understood.王先生反复地解释直到学生听懂了为止。注意：①until在肯定句中只与延续性动词连用，在否定句中通常与非延续性动词连用，表示相应动作开始的时间，意为“直到……才”。如：He didn't leave until I came back.直到我回来他才离开。②till用作连词，与until同义，两者经常可换用，只是 until 比 till 稍正式。在正式文体中，一般用 until，而在口语或非正式文体中则两者都可。till多与名词或较短的从句连用，而较长较复杂的成分多用 until；在句子开头时，用 until而不用till。如：She lived in Tokyo till （until）she died.她一直住在东京直到去世。（√）Until he comes back，nothing can be done.在他回来之前，什么也不能做。（×）Till he comes back，nothing can be done.在他回来之前，什么也不能做。（5）since引导时间状语从句意为“自……以来”Since I left school，I have written to him twice.自从我离开学校以来，我已经给他写过两封信。I have not heard from him since he left Shanghai.自从他离开上海以来，我就没有收到过他的来信。注意：since引起的时间状语从句通常用一般过去时态，主句用现在完成时态。如：I've worked here since I left school.自我离开学校以来我一直在这里工作。（6）as soon as引导时间状语从句意为“一……就……”I'll tell you as soon as I get here.我一到这里就告诉你。I want to see him as soon as he arrives.他一到我就想见他。2.时间状语从句的时态（1）当主句的谓语动词是一般将来时，由when，before，after，as soon as，until 等连词引导的时间状语从句用一般现在时。如：I 'll tell him the good news as soon as I see him.我一见到他，就告诉他这个好消息。The boy will be a writer when he grows up.这个男孩长大后将成为一名作家。（2）当主句的谓语含有can，may，must等情态动词时，由when，before，after，until，as soon as等引导的时间状语从句用一般现在时。如：You can go home after you finish your homework.你做完作业后就可以回家。When the lights are red，the traffic must stop .红灯亮时，车辆必须停下。You may wait here before your father comes .在你父亲到来之前你可以在这儿等着。（3）当主句的谓语是want，hope，wish等动词的一般现在时形式时，由when，before，after，until，as soon as等引导的时间状语从句用一般现在时。如：He wants to be a doctor when he grows up.他长大后想当一名医生。She wants to work in America when she finishes college.她大学毕业后想在美国工作。（4）当主句是祈使句时，由when，before，after，until等引导的时间状语从句用一般现在时。如：Don't get off the bus until it stops .公共汽车停下来再下车。Please don't go to bed before you finish your homework.在完成作业之前，请不要睡觉。（5）当主句谓语用一般过去时，由when，before，after，until，as soon as等引导的时间状语从句也要用一般过去时。如：They talked about the party after people left .人们离开后，他们谈论这次晚会情况。（6）当before引导的时间状语从句是过去时态，主句一般用过去完成时，有时也用一般过去时。如：She had learned Japanese for three years before she went to Japan.她去日本之前学了三年日语。She didn't know me before she came here.她到这里来之前不认识我。（7）since引导的时间状语从句要用一般过去时，主句的谓语动词要用延续性动词，通常用现在完成时；用非延续性动词时，要用否定式。如：He has waited here since you left .自从你走之后他一直在这等着。He hasn't gone to the school since he finished the school.他毕业后再没去过学校。注意：在It is+时间+since从句结构中，主句用一般现在时，从句用一般过去时。如：It is three years since I began to study English.我开始学英语已经有三年了。3.时间状语从句的位置（1）when，before，after，as，while，as soon as等引导的时间状语从句的位置可位于句首，也可位于句末。放在句首时，从句后通常用逗号与主句隔开，放在句末时，从句与主句之间一般不用逗号，只在句末用句号或问号。如：When you came to see me，I was ready to leave.你来看我时，我正准备离开。You called me while I was watching TV.我在看电视时，你给我打了电话。After she cleaned the classroom，she went home.她打扫完教室后回家了。（2）since引起的时间状语从句通常放在主句的后面。I have learned English since I came to this school.我自从来到这个学校以来就一直在学英语。