If you have studied Chinese for 4 or 5 months, you probably know míngbái ( 明 白 ), a Chinese word meaning ‘clearly understood.’ Bù míngbái ( 不 明 白) is what you say when you aren’t quite sure or you are confused about the meaning of something. Wǒ bù míngbái (我 不 明 白) (I’m not clear).
When you are not clear about what your are hearing or reading, you can either apologize (Duìbuqǐ) (对不起) (which also means ‘excuse me’) and say “Wǒ bù míngbái“ (我 不 明 白) and/or politely ask him to explain a little (Qǐng nǐ jiěshì jiěshì) (请 你 解 释 解 释). However, you would NOT want to ask someone to speak míngbái yīdiǎnr (speak it out a little clearer), because it would imply he is hiding something or lying.
A fun idiom is bù míng bù bái (neither clear nor white) ( 不 明 不 白 ) , used to refer to hazy written or spoken ideas, speeches, talk, rules, or even behavior. Laws are sometimes bù míng bù bái so that power can overrule law, when convenient.
One song shows you another way to use míngbái. The lyrics are written out in pinyin and translated into English in the notes.
There is another song called Ming Ming Bai Bai Wo de Xin. You can Youtube it, if you want. See how it’s translated.