"Tomorrow is another day" is a quote from the movie "Gone With the Wind". It means you hope that things will get better tomorrow, or you'll have another chance to make things better tomorrow.

Whatever happened today is not going to stop the sun from shining tomorrow...and you can try again. Life goes on... you'll have more opportunities (tomorow) ^^ In Spanish we say : "Mañana será otro día "

Hello 百鬼夜行, In Chinese, you can express it using "明天又是新的一天". It means that tomorrow you can start all over again, or start a new thing even if you haven't been successful until now. You shouldn't lose faith. Nobody knows what will happen tomorrow, so... everything is still possible! "人生在世,难免会有诸多不能承受之重。无论生活在哪个时代都不容易,大萧条时期也好,鼎盛时期也罢。这句话都适用于每一个人面对困难,永不低头、永不退缩,以积极的态度去迎接挑战。在世界改变的时候也要适时地改变自己去适应这个世界,只有持有这样生活态度的人,才有资格站在困难面前,被称为强者。[...] 所以,当我们在承受苦难的时候何不对自己大声说:“明天又是新的一天”。一个充满希望、充满挑战、充满机遇和无限魅力的一天啊! "

When I saw the film "Gone With the Wind" I recalled another expression from the Bible (Mat.6:34). It says:"Therefore do not be anxious about tomorrow, for tomorrow will be anxious for itself". You can look at it in its context - http://www.biblegateway.com/passage/?search=Matthew+6&version=ESV

This means that tomorrow will bring something new. Sometimes people say it when they are having a difficult time with something. Then they'll say "tomorrow is another day" = it'll be different. "Don't worry. Tomorrow is another day. Everything will be better then." A lot of (older?) US speakers know this from the movie "Gone with the Wind." At the end of the movie the main character's husband (boyfriend?) leaves her and she is upset, but she decides she'll go back to her home and says this. You hear her say it at about 8:28 in this clip. http://www.youtube.com/watch?v=yBH2i8WmcU8&NR=1