So that的用法

So that 的用法总结
有这样一个句子：If you press another (button), your meal is prepared and heated for you; then it is brought on along a very small railway line to your seat in front of your television, so that you do not even have to stand up when you want to get what you need. 句中so that 的意思和用法很容易被师生忽略。

于此，就其用法作一诠释。

So that 作为从属短语连词，即可以引导目的状语从句，也可以引导结果状语从句，但差异较大。

一、引导目的状语从句
So that“以便，为了”，引导一个表示目的的状语从句，此时可与in order that 换用；从句谓语动词中常用情态动词may/ might, can/ could, should, would等；主从句间连接紧凑，没有逗号相隔。

My old father began to study computer at the age of sixty so that (= in order that ) he might keep up with time.
父亲六十岁时才开始学电脑，以便跟上时代。

I spend more time learning English every day so that (= in order that ) I can make greater progress this year.
为了今年取得更大进步，我每天用了更多的时间学英语。

二、引导结果状语从句
So that “因此，所以”，引导一个表示结果的状语从句，此时不能与in order that 换用；从句中谓语根据需要使用相应的事态，主从句之间可有逗号相隔。

本文开头所列举例子中so that 就是这种用法。

又如：
She had not planned her time well, so that she did not finish her homework on time.
她没把时间计划好，所以没按时完成家庭作业。

Wang Lang did not work hard enough, so that she is out of work when she is still young.
王朗工作不够努力，因此，年轻时就失业了。

三、辨别两种不同状语从句
1）根据句子结构辨别：从句谓语中含有情态动词may/ might, can/ could, should, would等，这时so that 引导的是一个目的状语从句；从句前面有逗号和主句相隔，此时so that 引导的是一个结果状语从句。

试对比以下两个例句：
Yesterday morning Yang Cheng got up early so that she could catch the first bus.
昨天早上扬程为了赶上早班车起床很早。

Yesterday morning Yang Cheng got up early, so that she caught the first bus.
昨天早上扬程起床很早，因此，她赶上了早班车。

2)根据主从句逻辑关系辨别：so that 引导目的状语从句，一般表示尚未完成的目的或意图，主句和从句之间是结果与目的的关系；而so that 引导的结果状语从句则是表示主句所导致的结果，主句和从句之间是原因与结果的关系。

试比较：
I tell my students my new telephone number so that they may call me when necessary.我把新的电话号码告诉学生以便必要时他们给我打个电话。

I told my students my new telephone number so that all of them called me when necessary. 我把新的电话号码告诉了学生，因此，必要时他们都给我打了电话。

四、同其他结构转换
So that 引导目的状语从句时，可以与表示目的的动词不定式（not) to do.../ in order(not) to do...互换。

但主从句主语须一致（句①②），否则不能转换（句③）。

① We went to the airport so that we might meet Professor Yang there.
—We went to the airport to meet Professor Yang there.
—We went to the airport in order to meet Professor Yang there.
—We went to the airport so as to meet Professor Yang there.
② They had to walk a long way to/ in order to / so as to fetch some firewood.
—They had to walk a long way so that they might fetch some firewood.
③ Mr.Cheng turned up the recorder so that every student in the classroom could hear clearly. (主从句主语不一致）
1.You must explain that contribution so that people can understand it.
你必须解释这个思想贡献，这样，人们才能理解他。

2.Would you tell us what quantity you require so that we can work out the offers?
为了利于我方提供报价，能否请你谈谈你方所需的数量。

3.Now, perhaps the laws should be altered so that every wizard could magically create what they need?现在，或许法律需要被改变来使巫师能用魔法创造他们想要的东西么？
4.Our goal is to win the World Cup, and we have declared that early so that the players learn to dealt with that expectation.
我们的目标是世界杯冠军，我很早就告诉了他们，目的也就是希望他们学会正确地处理好这种期望。

5.I study hard so that I may not fail in the examinations.
我用功，免得考试不及格。

6.We turned on the light so that we might see (so as to see) what it was.
我们把灯打开，一遍看看它是什么。

7.Bring it closer so that I may see it better.
把它拿近点儿，让我仔细看看。

8.They put a screen around his bed so that the doctor could examine him.
他们在他床的四周放上屏风，以便医生给他检查。

9.The term and condition are printed in very small letter so that they are difficult to read.
条款与条件是用很小的字体印刷的，以致难以阅读。

10.She simplified the instructions so that the children could understand them.
她简化了指令以便于儿童理解。

11.Making something by hand has become the exception in many countries today--so much so that giving a homemade gift is sometimes considered extraordinary.
当今用手做东西，在许多国家已经成为很特殊--如此地特殊，以致赠送自制礼物有时被认为是不寻常的。

12.We made a strategic withdrawal, so that we could build up our forces for a renewed attack.
我们做了一次战略性退却，以便我们能积蓄力量再次进攻。

2013年10月1日。