初中英语连词归纳.ppt

初中英语连词归纳.ppt连词
连词的功能
用来连接词,短语,从句或句子的词叫连词。连词是一种虚词,在句中不能单独使用。连词可分为两类:并列连词和从属连词。
并列连词
并列连词用来连接具有并列关系的词,短语或句子。常见的并列连词有:
(1)表并列关系的and, both…and, not only…but also, neither…nor等。
(2)表选择关系的or, either…or等。
(3)表转折关系的but, while等。
(4)表因果关系的for, so等。
从属连词
从属连词用来引导从句。常见的从属连词有:
(1)引导时间状语从句的after, before, when, while, as, until, till, since, as soon as等。
(2)引导条件状语从句的if, unless等。
(3)引导原因状语从句的because, as, since等。
(4)引导目的状语从句的so that, in order that等。
(5)引导让步状语从句的though, although, even if等。
(6)引导结果状语从句的so that, so…that, such…that等。
(7)引导比较状语从句的than, as…as等。
(8)引导宾语从句的that, if , whether等。
常用连词的用法辨析
(1) while, when, as
这三个连词都可引导时间状语从句,但用法有所不同。
1) 当某事正在进行的时候,又发生了另一件事。While, when, as 都可用来引导表示“背景”的时间状语从句。例如:
As/When/While I was walking down the street I noticed a police car.
2) 当两个长动作同时进行的时候,最常用的是while。例如:
While mother was cooking lunch, I was doing my homework.
3) 当两个动作都表示发展变化的情况时,最常用的是as。例如:
As children get older, they e more and more interested in things around them.
4) 当两个短动作同时发生时,或表示“一边…一边…”时,最常用as。例如:
Just as he caught the fly, he gave a loud cry.
She looked behind from time to time as she went
5) 当从句的动作先于主句的动作时,通常用when。例如:
When he finished his work, he took a short rest.
6) 当从句是瞬间动作,主句是延续性动作时,通常用when。例如:
When John arrived I was cooking lunch.
(2)as, because, since , for
这四个词都可表原因,但用法有区别。
1) 如果原因构成句子的最主要部分,一般用because。因此,because引导的从句往往放在句末。例如:
I stayed at home because it rained.
---Why aren’t you going?
---Because I don’t want to.
.
2) 如果原因已被人们所知,或不如句子的其它部分重要,就用as或since。Since比as稍微正式一点。As和since 引导的从句一般放在句子的开头。例如:
As he wasn’t ready, we left without him.
Since I have no money, I can’t buy any food.
3) for用来补充说明一种理由,因此,for引导的从句几乎可以放在括号里。For引导的句子不放在句子的开头。例如:
I decided to stop and have lunch----for I was feeling quite hungry.
(3)if, whether
if和whether都可作“是否”讲,在引导宾与从句一时般可互换。例如:
I wonder whether (if) you still study in that school.
I don’t know whether (if) he likes that film.
在下列情况下,只能用whether,不能用if:
1) 引导主语从句时。例如:
Whether he e to the party is unknown.
2) 引导表语从句时。例如:
The question is whether