内容正文:
第十四节 状语从句
【新手目标】
通过本关,你能够掌握时间,原因,目的,让步,结果,条件状语从句的分类及知识点。
关卡一 时间状语从句 ★★☆☆☆☆
【过关笔记】
1. 引导时间状语从句的连词
从属连词
用法
例句
While
When
As
Till/Until
Since
Before
After
【知识拓展】
时间状语从句的时态问题:在时间状语从句和条件状语从句中,主句如果使用一般将来时态,从句使用一般现在时表示将来,即所谓的"主将从现"。
As soon as I arrive in Beijing, I will ring you up. 我一到北京就给你打电话。
You’ll fall behind the others unless you study hard. 如果你不努力学习,你将会落后于其他人。
2. when,while,as引导时间状语从句的区别
① when可以和延续性动词连用,也可以和短暂性动词连用;而while和as只能和延续性动词连用。
Why do you want a new job when you’ve got such a good one already?
你已经找到如此好的工作,为何还想再找新的? (get为短暂性动词)
Strike while the iron is hot. 趁热打铁。 (is为延续性动词,表示一种持续的状态)
The students took notes as they listened. 学生们边听课边做笔记。 (listen为延续性动词)
② when从句的谓语动词可以在主句谓语动作之前、之后或同时发生;while和as从句的谓语动作必须是和主句谓语动作同时发生。
a. 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. (finished先发生)
当他完成作业后,他休息了一会儿。
When I got to the airport, the guests had left. (got to后发生)
当我赶到飞机场时,客人们已经离开了。
b. 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。
①When / While / As we were dancing, a stranger came in. (dance为延续性动词)
②When / While / As she was making a phonecall, I was writing a letter. (make为延续性动词)
c. 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. 随着时间的过去,天气变得更糟糕了。
The little girls sang as they went. 小姑娘们一边走,一边唱。
3. 比较until和till
此两个连词意义相同。肯定形式表示的意思是"做某事直至某时",动词必须是延续性的。否定形式表达的意思是"直至某时才做某事"。动词为延续性或非延续性都可以。正确使用这两个连词的关键之一就在于判断句中的动词该用肯定式还是否定式。
区别:
(1)until可用于句首,而till通常不用于句首。
Until you told me, I had heard nothing of what happened.
直到你告诉我以前,出了什么事我一点也不知道。
(2)It is not until... that...
It was not until I began to work that I realized how much time I had wasted.
4. as soon as引导的时间状语从句
as soon as 一....就...,强调动作紧密相连。
主从句时态:
①主句一般过去时,从句一般过去时。
②主语一般将来时,从句一般现在时。
【成长例题】
例题1(2020秋•老边区校级月考)Mr Green asks us to hand in our reports ______ we finish them.( )
A.before B.as soon as C.th