介词短语做定语和状语的区别(分析一些for的句子)

修饰名词的就是定语,修饰动词或形容词的就是状语.如：
The reason for his being late was that he missed the bus.他迟到的原因是没赶上公共汽车.
（for his being late修饰reason,是定语.）
Could you buy a towel for me?你可以给我买一条毛巾吗?
（for me修饰动词buy,是状语.）