“班門弄斧”，意思是“在魯班門前舞弄斧子（show off one's proficiency with the axe before Lu Ban， the master carpenter）”。比喻在行家面前賣弄本領(lǐng)，不自量力（show off in the presence of an expert；be conceited），與英文習(xí)語“teach one's grandmother (how) to suck eggs”意思相近。

魯班是中國古代杰出的土木工程師和木匠（outstanding civil engineer and carpenter），他被尊稱為土木建筑鼻祖、木匠鼻祖。

例句：

tā zǒng shì gào sù shàng sī zěn yàng jīng yíng shēng yì，jiǎn zhí shì bān mén nòng fǔ
他總是告訴上司怎樣經(jīng)營生意，簡直是班門弄斧。
He is always telling the director how to run the business that's like teaching his grandmother to suck eggs.

bù yào bān mén nòng fǔ，bào bó yǐ jīng dǎ le hěn duō nián wǎng qiú le
不要班門弄斧，鮑勃已經(jīng)打了很多年網(wǎng)球了。
Don't teach your grandmother to suck eggs. Bob has been playing tennis for years.

Editor: Jade