共同点是都能引导状语从句，不同点是引导不同类型的状语从句 so that:为了，引导目的状语从句 The new company gave away lots of ads so that people can get to know it. 这家新公司散发了大量的广告以便（为了）人们了解它。 so...that...: 如此。。以至于。。。，引导结果状语从句 The boy is so young that he can't go to school. 男孩太小了以至于不能去上学。 OK？
1 so that 引导目的状语从句时,表示“以便；为了”,从句中常使用can /could /may /might /will /would /should等情态动词或助动词；引导结果状语从句时,从句中一般不用can和may等词,在so that前可以用逗号,意思是“因此;所以”.如：The little boy saved every coin so that he could buy his mother a present on Mother's day. 2 so ...that .. so＋形容词或副词＋that ...引导结果状语从句.意思是“如此……以致于……”.如：When the football fans saw Beckham,they got so excited that they cried out.