in order to和so as to在用法上有什么区别?

问题描述:

in order to和so as to在用法上有什么区别?

in order to可以用在句首或句末,但so as to只能用在句末.
如:
He got up very early in order to/so as to catch the first bus.
In order to catch the first bus,he got up very early.(此时不能用so as to)