so as to与so...as to的区别

虽然so as to与so...as to在形式上差不多,而且后面都接动词原形,但它们表示的意思和在句中的作用却不同:前者表示“为的是; 是为了; 以便”的意思,与其后的动词原形一起作目的状语,用来强调目的; 后者表示“那么地……,以至……”的意思,so后面接形容词或副词,在句中as to和其后的动词原形一起作结果状语.例如:
Sometimes my friend goes to the library so as to borrow books.我朋友有时去图书馆为的是借书.
Tomorrow my father will go to Beijing so as to see his old friend.我父亲明天去北京是为了看望他的老朋友.
The girl was so excited as to shout herself hoarse.那个女孩兴奋得喊哑了嗓子.（或译为:那个女孩是那么地兴奋,以至于嗓子都喊哑了.）
He was so tired as to be unable to walk.（＝He was too tired to walk.）他累得走不动了.（或译为“他是那么累,以至于不能走路了.）
She is so wise as to solve the problem.她非常聪明,能解决这个问题.
The little boy ran so fastas to falldown.那个小男孩跑得太快,跌倒了.（或译为:那个小男孩跑得那么地快,以至于跌倒了.）
Yesterday morning I got up so late as to be late for school.昨天早晨我起得那么晚,上学都迟到了.
另外,还有三点需注意:
1.如果是表示否定目的,则要在“to”前加否定词not,即要用“so as not to”的形式.例如:
Let''''s hurry up so as notto be late for class.我们快点走吧,以免上课迟到.
Next week I am going to Beijing so as not to attend a meeting.我下星期去北京不是为了开会.
2.so...that 和so...as to虽然表示的意思几乎是一样的,而且两个so后面都是接形容词或副词,但它们所在的句子种类不同:前者所在句子是带结果状语从句的复合句,而后者所在句子是简单句.当复合句的主句和从句的主语相同,而且从句又是表示肯定意思时,两者可互换使用.例如:
Just now they were so happy that they jumped.可改为:Just now they were so happy as to jump.刚才他们高兴得跳了起来.
3.in order to是so as to的同义词组,两者一般可互换使用.但是,当特别强调目的,且把目的状语放在句首时,只用in order to.例如:
In order to realize our dreams earlier,each of us must study even harder.为了早日实现我们的理想,我们每个人都必须更加努力地学习.