一、Condition 条件/ 因为 (if )
后面跟随着某种情况发生的前提或者是条件。
if/unless/whether/provided that/Given that /for/so that/whether/depending on
1、if
例句与用法
He wondered if he had been dreaming . 他不晓得自己是不是做了一场梦。
You talk as if there were dangers . 你讲话好像有什么要大祸临头似的。
If you do not play , you will get out of practice . 不练习就会荒疏。
2、unless
例句与用法
Do n t come unless i ring you up . 除非我打电话给你，否则你不要来。
He ll certainly come unless he is ill . 除非他病了，否则他会来的。
3、provided that
例句与用法
I will come provided that i am well enough . 我身体好一定来。
Provided that she were sincere with me, i should forgive her a lot . 只要她对我真诚，我会宽容她的。
二、Time 时间 (when)
before/since/as/until/meanwhile/at the moment/when/whenever/as soon as/just as
1、before 例句与用法
I have heard that he has been married before .. 我听说他过去结过婚。
As i look back , scenes of the past leap before my eyes . 历历在目。
2、Since
例句与用法
Since i am not crazy, i do not care . 既然我没有发疯，我就毫不在乎。 He had changed, himself, since then .
从那时起，他自己也改变了很多。
3、until
例句与用法
They were silent until the drinks came . 酒送来之前，她们谁也没说话。
He had polished the table-top until it gleamed . 他把桌面擦到发亮。
三、Summary 总结 (in a word)
作后总结
in conclusion/in summary/lastly/finally/to sum up/to conclude/to recapitulate 重述/in short/in a word
1、in conclusion
例句与用法
he has been hurt already, said the old gentleman in conclusion . 他已经受了伤， 老绅士临了说。
In conclusion we note the following general items concerning flow in supersonic nozzles . 后，我们归纳几个关于超音速喷管流动的一般原则。
2、in summary
例句与用法
In summary there are the following possibilities for the observation of sunspots . 总而言之，对太阳黑子的观测存在着下列可能性。
But i can only tell you my situations in summary 但是我只能简略的告诉你我的情况
四、Example 举例 (for example) for example/for instance/just as/in particular/such as/namely 也就是
1、for example 例句与用法
Great men have often risen from poverty -- lincoln and edison , for example . 大人物常常出身贫寒，例如林肯和爱迪生。
Some appliances, for example a water heater, are connected to the full 240 v . 有些用电设备（如煮水器）联接在240伏上。
2、For instance
例句与用法
For instance , one of our cargo ships sank last week in typhoon . 例如，我们的一艘货轮上星期在台风中沉了。
For instance explore the question does diet influence heart disease? 例如探讨这样一个问题， 膳食影响心脏病吗？
五、Reason 原因 (because)
since/as/so/because (of)/due to/owing to/the reason why/in other words/leads to/cause
1、due(户籍所在地怎么填写？户籍所在地是指我国居民户口簿登记所在地，一般是指出生时其父母户口登记地方。按照户口登记管理条例，公民填写户籍所在地，应该填写到户籍管理机关所在地，即城市户口的应该填**省**市(县)**区;农村户口的应该填**省**县**乡。一般在填写户籍所在地时，只填写到县就可以了。) to
例句与用法
The wage due to him will be paid tomorrow . 他应得的工资明天付给他。
Opacity is due to crazes in the resin . 不透明是因树脂中产生裂纹。
2、because of
例句与用法
This blanket is warm because of its thickness . 这毛毯因为厚而很暖。
The earth is round because of gravity . 地球是由于重力而成为球形的。
3、In other words
例句与用法
In other words it has a large automorphism group . 换言之，它有大的自同构群。
In other words polarization properties are excluded . 换句话说，偏振性质未包括在内。
In other words such a molecule is pictured much as if it were a conducting helix . 换句话说，这样一个分子的图象很像一条导电的螺旋线。