1. 目的状语从句表目的,其关联词有:
so, that, so that, in order that, in case, lest, for fear that等。
I gave you a map so you wouldn't get lost.我给你一张地图,这样你就不会迷路了。
They set off half an hour earlier that they might get there in time.他们早出发半小时,以便及时到达那里。
I am saving money so that I can buy a house.我正在攒钱,以便买一所房子。
Would you add in these items,please,in order that we complete the list?为完成整个目录的编写工作,请你把这些条目加进去好吗?
Take warm clothes in case the weather is cold.穿上暖和的衣服,以防天冷。
I ran as fast as possible lest I should be too late.我尽量快跑,免得迟到。
We spoke in whispers for fear that we might wake the baby.我们轻声说话,以免吵醒婴儿。

2. 目的状语从句中常用情态动词may/might,shall/should,will/would和can。
Bring it closer so I may see it better.把它拿近点,我好看清楚。
I'll ring him up at once so he shouldn't wait for me.我马上给他挂电话,让他别等我了。
I will give you all the facts so that you can judge for yourself.我会给你所有的事实以便你可以自己判断。

3. 目的状语从句多置于主句之后。so that和in order that引导的从句如被强调则可置于句首。
We hid it carefully so that no one should see it.我们把它藏得很好,没有人会看到的。
He did that in order that everyone should be satisfied.他那样做是为了让大家都满意。
So that the coming generation can learn the martial arts,he has recently devoted much time to writing books on the subject.为了下一代能够学会这些武术,他近来花了许多时间著书立说。
In order that the grass and flowers could bloom again,it was necessary that the rocks should be removed. 为了这些花草能再开花,这些石头必须搬走。

4. lest引导的从句中谓语动词要用虚拟语气(should+动词原形);in case引导的从句中谓语动词可用虚拟语气,也可用陈述语气。
Be careful lest you (should) fall from the tree.小心,不要从树上掉下来。
Be quiet in case you wake the teacher.轻点儿,别弄醒老师。
Keep the window closed in case it rains.把窗户关好,以防下雨。