班门弄斧 bān mén nòng fǔ

DEFINITIONS

  1. to display one's slight skill before an expert (idiom)

CHARACTERS

班 bān class, group, grade; squad; job
门 mén gate, door, entrance, opening
弄 nòng do, play or fiddle with; alley
斧 fǔ axe, hatchet; chop, hew