深藏不露

shēn cáng bù lù

hiding one’s true abilities

Character by character

深shēn
deep

藏cáng
hide

不bù
not

露lù
show

没想到他钢琴弹得这么好，真是深藏不露。

Who knew he played piano so well — a real dark horse.

Tone: neutral.

Said in surprise when a quiet person turns out to be highly skilled; 露 is lù.

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