不定式作状语
不定式作目的状语:
He broke into the house to steal something.
to do ,in order to do,和 so as to do都可用来引导目的状语从句
She studied very hard in order to catch up with others.
Let’s hurry so as to go to school in time.
注意:in order to 可用在句首和句中而 so as to只能用在句中而不能用在首。