常用状况下：
1．so that引导目的状语从句． 意思是：以致，为了，以便于
2．so....that 引导结果状语从句．意思是：如此．．．以致
详细用法请见：参考资料里的链接网址（这里说的特别详细，而且有助于大家更好的理解这2个词组的在不同时态下的用法。）
一、“so…that”结构表示“如此……以致”时，so后跟形容词或副词，that后引出结果状语从句。例如：
1、I was so busy at that time that I didn't go to sleep for three days.那时我很忙，一连三天都没睡觉。
2、The noise was so loud outside that I could sleep no longer.外面的噪声这样大，我再也睡不着觉了。
3、The pop star sang so beautifully that he was asked to sing again and again.
歌星唱得这样好，人们要求他唱了一首又一首。
4、The weather is so cold that they had to stay at home.天气如此冷，以至于他们不得不呆在家里。
5、The coat is so expensive that I don't want to buy it.这件外套太贵，我不想买。
6、He was so sad that he began to cry. 他悲伤得哭了起来。
二、so that意为“以便；以使”，引导目的状语从句。例如：
1、I raised my voice so that I can make myself heard.我提高了声音，以便让大家都能听到我的话。
2、Bob invited world-famous singers to sing for free so that he could collect money for the hungry people.
鲍勃邀请那些世界闻名的歌手来义演，为的是替饥民们筹款。
3、He unlocked the bike so that he can use it at any time. 他没有锁车,为的是随时都能用.
4、I put on a red coat so that he could see me easily. 我穿了一件红外套以便他能很容易地看见我。
5、They bought some more presents so that each of us could have one.
他们又买了一些礼物,为的是我们每人都能有一份。
参考资料
“so that”与“so…that”的用法归纳.英语语法网[引用时间2017-12-20]