四个词在做连词“因为”讲时,用法有些区别:
1. because的语气特别强烈,用来引导直接的、具体的和明确的原因,用来回答以“why”开头的特殊疑问句,一般放在主句之后,because引导的从句放在前面时应在主句和从句之间加一个逗号。例如:
(1)A: Why are you late again?
B: Because the traffic is bad.
(2)He didn’t come with me because he had a lot of things to do. (= Because he had a lot of things to do, he didn’t come with me.) 他没有和我一起来,因为他有很多事情要做。
注: 对于以why开头的问句,一般只能用because引导的从句来回答。
2.since相对于because来说语气弱一点,侧重主句,从句表示显然的或已经知道的理由。例如:
(1)Since he asks, I will tell him. 既然他问,我就告诉他。
(2)Since Sandy is busy working during the day, she has to study at night. 既然桑迪白天忙于工作,她只好在晚上学习。
since表示原因时,语气比because弱,表示的原因是对方已知的,所说明的原因有时不是根本的或直接的原因,是附带的原因,一般把它译成“既然”。since比as稍微正式一些。since引导的从句一般放在主句之前。例如:
Since this method doesn\'t work, let\'s try another.
3.as相对于since来说语气弱一点,着重从逻辑和推论方面来说明或引出结果,主句与从句并重,主句说明结果,从句说明原因。例如:
(1)As you know everything, I want to say nothing. 因为你已经知道了一切,我就不想说什么了。
(2)I didn’t ring you up as I know you were not at home. 我没有打电话给你因为我知道你不在家。
as用来表示原因时,只说明一般的因果关系,语气没有because重,它所引导的从句,可放在主句之前,也可放在主句之后。例如:
You needn’t go with me, as you are busy.
As I was afraid, I hid myself.
4.for表示所说的理由是一种补充说明,因此,for引导的从句可以放在括号里,而且for引导的从句一般不放在句子的开头。例如:
I decided to stop and have lunch, for I was feeling quite hungry. |