i'm supposed to be running和i am supposed to run的区别?

问题描述:

i'm supposed to be running和i am supposed to run的区别?

正在和一般的区别.
被期望在某时间正在做某事
被期望做某事
若没有特定的时间限制(如 at that moment \ second之类的),常用后面那个吧.我觉得~