Hey Sri. I don't think there is an official time for dividing evening and night but usually "evening" is the time when it starts getting dark outside and before you go to bed. For instance 6-10pm would be a good estimate, anytime after that and while you are asleep would be considered ''night''. Just remember ''evening'' comes before ''night''. "Evening'' also sounds a bit more formal in certain contexts. Also, when used as a greeting, ''good evening'' is usually used to say ''hi'' and ''good night'' is more of a farewell. Hope that helped. :)

I would say that "evening" is the time from sunset until it's completely dark, and "night" is the time when it is completely dark. Sometimes people also use the word "evening" to refer to the part of the night that comes before midnight.

Evening is usually 4:30 - 8:00, after that it is night. (Those aren't exact times, but around those times)

Evening is absoultely before night. in the evening https://images.search.yahoo.com/search/images;_ylt=AwrB8ptcmA5TfXgA.oeJzbkF?p=in+the+evening&fr=yfp-t-901&ei=utf-8&n=60&x=wrt&y=Search at night https://images.search.yahoo.com/search/images;_ylt=AwrB8ptcmA5TfXgA.oeJzbkF?p=at+night&fr=yfp-t-901&ei=utf-8&n=60&x=wrt&y=Search

I still confused explaining to the students with the difference between evening and night especially when doing english test especially reading comprehension for junior high school students.