1. since 自从，从……以后：

　　They have been close friends since childhood.

　　他们从小就是好朋友。

　　She has lived here since 1990.

　　她从1990 年起就在这里住。

　　I haven't been out much since coming here.

　　来这里之后我没太出去。

　　Since when have you been working on this project?

　　你从什么时候起搞这项研究工作的?

　　This has been my ideal since long ago.

　　好久以来这一直是我的理想。

　　2. through:

　　l)穿过，通过(某地):

　　what's the place we're passing through?

　　我们正在经过的是什么地方?

　　We helped her get out through the back door.

　　我们帮助她从后门逃出。

　　There is a path through the fields.

　　穿过田野有一条小路。

　　2)经历过：

　　She must have been through a lot.

　　她一定受过很多苦。

　　They went through many trials.

　　他们经历过很多考验。

　　She told us about the hardships she had been through.

　　她跟我们谈了她受过的苦。

　　3)通过(某人或某事):

　　We learnt all this through John.

　　这一切我们都是从约翰那里知道的。

　　We learn to speak through speaking.

　　我们通过说话学说话。

　　He obtained the work through his own efforts.

　　他是通过自己的努力得到这份工作的。

　　4)由于：

　　The war was lost through bad organization.

　　由于组织不好，战争打败了。

　　They lost the match through over-confidence.

　　由于过于自信他们赛输了。

　　5)用于某些成语：

　　We quickly saw through his trick.

　　我们很快看穿了他的鬼把戏。

　　So they got through it as quickly as possible.

　　于是他们尽快把它干完。

　　He began to look through the photograph album.

　　他开始翻阅像册。

　　She read through three of the passages.

　　她看完了三段。

　　He was ill all through November.

　　整个十一月份他都在生病。

　　I'll like you to go through my book.

　　我想请你把我的练习看一遍。

　　They stuck together through thick and thin.

　　他们同甘共苦一直待在一起。