Bis morgen - the one you talked with expect that he will meet you at next day. Bis morgen ? - the one you talked with is not sure if he meets you next day and aked you. Example - monday at school you say - bis morgen - couse you will be there next day and the one you talked with, also. friday at school - bis morgen ? - maybe you want to see the person next day, but there is no schoolday - so at home ? ore else.

morgen = tomorrow = 明天 Der Morgen = the morning = 早 / 上午 It means: 'See you tomorrow.' 明天见. "Auf Wiedersehen!" doesn't say when you will meet again. "Bis Morgen!" means you will see each other tomorrow (in the morning or at any other time of day).

Doom hat eben recht. "Bis morgen" heisst 明天见。