班門弄斧 [－门－－]

Jyutping baan1 mun4 lung6 fu2
Pinyin bān mén nòng fǔ

Definitions (CC-CEDICT)
  1. to display one's slight skill before an expert (idiom)
Definitions (粵典–words.hk)
  1. 語句
    喺​啲​老​行尊​面前​賣​弄​自己​功夫
    to show off in front of an expert; to teach a fish how to swim
Definitions (Wiktionary)
  1. phrase, idiomatic
    to show off one's inferior talent or skill in front of an expert
    (syn.) 關公面前耍大刀, 关公面前耍大刀
Definitions (Kaifangcidian)
  1. （沒有對應漢語詞彙）