hide one’s light under a bushel;not to show off one’s knowledge ? 他的朋友們都勸他小心謹(jǐn)慎，～。All his friends advised him to be very cautious and hide his light under a bushel.
不露圭角bù lù ɡuī jiǎo
形容不露鋒芒。hide one’s light under a bushel, not to show off one’s knowledge