so that.so that是从属连接词,却具有对等连接词,接续前文的意味(so …,所以)；so … that …中that 是从属连接词,so 却是副词；
such that也是从属连接词,意为"这麼一来就...(in such a way that)"；such … that…中that是从属连接词,such 却是形容词,
其中so that既可省略so亦可省略 that,其语意和such that其实不尽相同；as … that …中that 是从属连接词,as 也是从属连接词,取代so的用法,如同取代 though / althouth一般.
She works very hard so that she is sure to be successful.她很努力所以她一定会成功
She works very hard such that she is sure to be successful.她很努力这麼一来她势必会成功