Grammar1

Music Born in America语法学案命制：魏淑慧审核：牟慧芳班组：姓名：组评：师评：学习目标：☆知识目标：巩固时间状语从句并归纳各种时间的表达法；☆能力目标：认识省略现象.☆情感目标：温故知新，学以致用。

（一）Adverbial clauses of time (时间状语从句)一．常见引导词；when, while, as(当…时); as soon as, the moment, directly, immediately(一…就); until, till(直到); before(在..之前); after(在…之后); since, ever since(自…以来); once(一旦); whenever(任何时候); every time, each time(每次).二．解析：⑴when 的用法①When 引导的时间状语从句的谓语动词可以是延续性的，也可以是非延续性的，既可以是从句动作与主句动作同时发生，也可表示从句的动作先与主句动作发生。

When he reached home, it was getting dark. (主从句动作同时发生)I shall tell her the good news when she comes. (从句动作先于主句动作发生)②当when 引导的从句谓语动词是延续性的，when 类似于while.When (while) he was crossing the road, he was knocked down by a passing car.③when 还可以做并列连词，表一个动作即将或正在进行的时候，突然发生了另外一件事。

其意义为“那时”“这时”，相当于at this\ that timeWe were having a meeting when someone broke into.We were about to go out, when it suddenly began to rain.④when 还可表原因“既然”It was foolish of you to take a bus when you could easily walk there in five minutes.⑵while的用法①while 引导的从句谓语动词为延续性的，表示“与……同时”“在……其间”从句常用进行时态，强调某一时间内主句和从句的动作同时发生。

Someone knocked at the door, when (while) I was watching TV.Strike while the iron is hot.②while 有时可以表示前后两种情况进行对比，作为并列连词“而，却”He likes pop music, while I am fond of folk music.③While 放在句首引导从句，译为“尽管”While I think you idea is good, I don’t quite agree with everything.⑶as的用法as 表示“当……时候”或“一边……一边”，as 的从句中可使用延续性动词，也可使用非延续性动词。

He sang as he was working.As time goes by, we have a better understanding of things around us.As I get older, I get more optimistic. (4) till, until 引导的时间状语从句①till 引导的时间状语从句主句的动词常是延续性的。

而not…until 引导的时间状语从句主句的动词常是短暂性的We will stay here till\until it stops raining.John did not announce the news till he was sure of it.②Not until 置于句首时，主句的主语和谓语要倒装，表示加强语气。

Not until Mary had heard that sound was she really frightened.(5) as soon as, immediately, directly, once, the instantly, instant ly, no sooner……. than, hardly \scarcely……when 引导的时间状语从句，表示“一……就……”I came immediately I got your message.Once you lose confidence, you won’t be able to do the work well.Jack had hardly\scarcely seen me when he left the classroom.※当no sooner, hardly, scarcely 置于句首时，主句要部分倒装.Hardly\scarcely had we gathered in the wheat when it began to rain.No sooner had we arrived at the station than the train left.(6) before 和since①若表达“还未……就…; 不到……就，……才……，趁，还没来得急”时，需用连词before.We had sailed four days and four nights before we saw land .我们航行了四天四夜才看到了陆地。

We hadn’t run a mile before he felt tired.我们跑了还不到一英里他就累了。

Please write it down before you forget it.趁你现在还没忘，请把记下来。

Before I could get in a word he had measured me .我还没来得及插话，他就给我量了尺寸。

②before 在从句中谓语动词不用否定式。

Before they reached the station, the train had gone.他们（还没）到火车站以前，火车就开走了。

③．It will be + 一段时间+ before… 多久之后才。

It will be half a year before I come back.④在“It is + 一段时间+ since 从句”句型中，时间的计算一律从动作完成或状态结束时开始。

从句动词是短暂性动词按原意思翻译，延续性动词按相反的意思翻译。

It is three years since the war broke out.战争爆发以来三年了。

It is three years since he lived here.他离开这里三年了。

（二）Ellipses (省略)1. 简单句中的省略1)省略主语祈使句中的主语通常被省略。

如:(You) Open the door, please. 请开一下门。

其他省略主语多限于现成的说法。

如:(I) Thank you for your help 谢谢你的帮助。

(It) Doesn’t matter. 没关系。

2)省略主谓语或主谓语的一部分如:(There is) No smoking. 禁止抽烟。

(Is there) Anything else? 还有其他事吗？(You come)This way please. 请这边走。

(Will you) Have a smoke? 抽烟吗？3)省略宾语。

如:—Do you know Mr. Li?你认识李先生吗？—I don’t know (him. )我不认识他。

4)省略表语。

如:—Are you thirsty ? 你渴了吗？—Yes, I am (thirsty). 是的，我是。

5)同时省略几个成分。

如:—Are you feeling better now? 你觉得好些了吗？—(I am feeling ) Much better (now). 好多了。

(I wish) Good luck (to you). 祝你好运/祝你顺利。

2. 并列复合句中的省略在并列句中后边的分句可以省略与前边分句中相同的成分。

如:John came in April but Bob (came) in May.约翰四月份来的但鲍伯五月份来的。

The boy picked up a coin in the road and (the boy) handed it to a policeman.这小男孩在马路上捡到了一枚硬币并交给了警察叔叔。

Your advice made me happy but (your advice made) Tom angry.你的建议让我感到高兴但让汤姆生气。

3. 主从复合句中的省略1)状语从句中的省略一般说来省略现象多出现在下列五种状语从句中:由when, while, as, before, after, till, until, once等引导的时间状语从句；由whether, if, unless 等引导的条件状语从句；由though, although, even if, whatever等引导的让步状语从句；由as, than 等引导的比较状语从句；由as, as if, as though 等引导的方式状语从句。

上述状语从句在省略时应遵循下列规则:当状语从句的主语与主句的主语一致时，可以省略状语从句的主语和系动词be，这时从句中可出现如下结构:(1)连词（as, as if, once）+名词; (2)连词（though, whether, when）+形容词；(3)连词(whether, as if, while )+介词短语；(4) 连词(when, while, though )+现在分词；(5)连词(when, if, even if, unless, once, until, than, as )+过去分词；(6)连词(as if, as though )+不定式。

如:Once (he was) a worker, Pang Long now becomes a famous singer.庞龙曾经是一名工人，现在成了一名有名的歌手。

Work hard when (you are) young, or you’ll regret.趁你年轻时努力工作，不然你以后会后悔。

He looked everywhere as if (he was) in search of something.他四处张望好像在找什么。