in future; in the future辨识

in future意为"今后,从此以后",指从说话时开始的全部将来时间。如:

You can't go out alone in future. 今后,你最好不要单独外出。

in the future意为"将来,未来",指将来的某些时间,但不一定是从现在就立即开始。如:

My brother wants to be an actor in the future. 我弟弟将来想当一名演员。