词组短语
ever since adv. 从那时到现在
long since很久以前；从前
since when自什么时候起，打什么时候开始
同近义词辨析
because, for, as, since
这组词都有“因为”的意思，其区别是：
because从属连词，语意强，着重直接的原因或理由，所引出的从句是全句的重心，用以回答why提出的问题。
for并列连词，语气较弱，所引出的句子一般放在后面，表示附带说明的理由或推断理由。
as 从属连词，语意较because, since弱，着重在主句，所表示的原因或理由是“附带的”。
since语意比because弱，但比as强，一般用于表示“由于大家已知的事实”。
for, since
for 接一段时间 for three years,
since 接点时间或一句话，since 3:00
双语例句
用作连词(conj.)
- He must have taken the book since it isn't here.
他一定是把书拿走了,因为书已不在这里了。 - Since you can't answer the question, perhaps we'd better ask someone else.
既然你无法回答这个问题，我们最好再问问别人。 - He had spoken to her only once since the party.
自从那次聚会以来,他只跟她说过一次话。
用作介词(prep.)
- She's so easily fatigued since her illness.
自从病后，她很容易疲劳。 - She hasn't been out riding since the accident.
她自从出了事故以后，一直没有骑马外出过。
用作副词(adv.)
- Bows and arrows have long since been out of use.
弓箭很早以前就没人使用了。 - He left home two weeks ago and we haven't heard from him since.
他两星期以前离开了家，到现在我们一直没有他的消息。
权威例句
Advances in flavonoid research since 1992.ChemInform Abstract: Advances in Flavonoid Research Since 1992systolic blood pressure since 1980: systematic analysis of health examination surveys and epidemiological studies with 786 country-y...CHARLES HORNSBY, Kenya: a history since independence. London: I. B. Tauris (£45 – 978 1 84885 886 2)...Global analyses of sea surface temperature, sea ice, and night marine air temperature since the late nineteenth centurySericulture in Zhejiang Province Since China'Reform and Opening up(Ⅲ)——Development in Production Technology of Silkworm Eggs(Silk...Global, regional, and national causes of child mortality: an updated systematic analysis for 2010 with time trends since 2000.National, regional, and global trends in body mass index since 1980: Systematic analysis of health examination surveys and epidemiol...Rayner, N. et al. Global analyses of sea surface temperature, sea ice, and night marine air temperature since the late nineteenth ce...Henning Melber (ed.), Re-examining Liberation in Namibia: political culture since independence. Uppsala:...
