班門弄斧
simp班门弄斧baan1 mun4 lung6 fu2Bān mén nòng fǔ
English
- to display one's slight skill before an expert (idiom)
- to show off in front of an expert; to teach a fish how to swim (sometimes as a humble rhetoric)
粵語 — Cantonese
- 喺啲老行尊面前賣弄自己功夫(有時用作自謙)
Sources: cc-cedict, rime-cantonese, words.hk