不耻下问

bù chǐ xià wèn

not ashamed to learn from those below you

Character by character

不bù
not

耻chǐ
ashamed

下xià
downward

问wèn
ask

他虽然是教授，却不耻下问，常常向学生请教。

Professor though he is, he is not ashamed to ask and often consults his students.

Tone: positive (praise).

Only for a superior asking an inferior. Never say it of yourself asking a teacher.

Learn this in Lesson 206 · HSK 9+: 文言入门：之乎者也 (Classical Chinese: the four little words)

A dialogue, a reading, word cards with audio and a drill that uses it, in Learn Chinese with Bao. This lesson is free.