英语中morning night evening afternoon

There isn't exact dividing time line between any two of them.However,here in America,speaking of them,people usually refer them APPROXIMATELY to:
morning:before noon (12:00pm)
afternoon:12:00pm -- around 6:00pm
evening:6:00pm -- 9:00pm
night：9:00pm -- dawn

24:00-12:00morning(不包括24:00和12:00)
12:00-太阳落山前afternoon
太阳落山前-天黑evening
天黑-24:00night
12:00前后noon
24:00前后midnight

是模糊概念.没必要那么精确。

morning: 中午12点以前都可以叫morning
afternoon: 12点到18点
evening: 天黑以后到夜里12点
night：天黑以后到第二天天亮前
这些时间没有特别明确的界限，而且有些相互交叉。