◎ because,as和since是從屬連詞,引導(dǎo)原因狀語(yǔ)從句;for是并列連詞,連接并列分句。because用于回答why引導(dǎo)的疑問句,但as,since和for則不可以。
① because表示直接原因,語(yǔ)氣最強(qiáng),一般位于主句后,有時(shí)也置于主句前。
The teacher was angry because he was late again. 老師很生氣,因?yàn)樗诌t到了。
A:Why didn't you come?你為什么沒來(lái)?
B:Because I was ill. 因?yàn)槲也×恕?
② as用于解釋做某事的原因,語(yǔ)氣較弱,用于口語(yǔ),通常位于主句前。
As you are not feeling well today,you'd better stay at home. 既然你今天感覺不好,你最好待在家里。
③ since常指清楚的、雙方都明白的原因,語(yǔ)氣比because弱,但比as強(qiáng),通常位于主句前,并常同as換用。
Since/As you have finished your homework,let's go out to play. 既然你已完成了作業(yè),我們出去玩玩吧。
Since he can't answer the question,we'd better ask someone else. 他回答不了這個(gè)問題,我們就問別人吧。
④ for引導(dǎo)并列句,表示一種補(bǔ)充說(shuō)明,是推測(cè)或判斷的理由,語(yǔ)氣較弱,必須放在主句后面。
He must be ill,for he is absent from class today. 他一定病了,因?yàn)樗裉鞗]來(lái)上課。
We must start early,for we have a long way to go. 我們要早點(diǎn)動(dòng)身,因?yàn)橐吆荛L(zhǎng)的路。
⑤ because of是復(fù)合介詞,后跟名詞或代詞,也可跟what引導(dǎo)的名詞性從句。because of引導(dǎo)的短語(yǔ)只能作狀語(yǔ)。
They didn't arrive there on time because of the heavy rain. 由于天下大雨,他們沒有準(zhǔn)時(shí)到達(dá)那里。
He realized that she was crying because of what he had said. 他意識(shí)到,她是因?yàn)樗f(shuō)的話而哭的。
提示
on account of相當(dāng)于because of,但更為正式。
She stayed indoors on account of the bad weather. 由于天氣不好,她待在家里。
⑥ due to一般引導(dǎo)表語(yǔ),但引導(dǎo)狀語(yǔ)亦屬正確用法。
These slips are due to/owing to the author's insufficient acquaintance with the life of the labouring people. 這些疏誤是由于作者對(duì)勞動(dòng)人民的生活不夠熟悉而造成的。
⑦ owing to可用來(lái)引導(dǎo)狀語(yǔ)或表語(yǔ)(多用于前者)。owing to一般是修飾整個(gè)句子,因此嚴(yán)格來(lái)講,應(yīng)用逗號(hào)和前面的句子分開,在這點(diǎn)上不同于because of,后者可以僅修飾句中的一部分,見上例,中間不用逗號(hào)。
They decided to put off the trip,owing to the change of weather. 由于天氣變化,他們決定延期啟程。