lu ban was supposed to be a consummate1（至上的，完美的） carpenter in ancient times. it is said that he once carved a wooden phoenix2（凤凰） that was so lifelike（逼真的） that it actually flew in the sky for three days. thus it was considered the height of folly3 to show off one's skill with an axe4 in front of lu ban.
this idiom excoriates5（批判） those who show off their slight accomplishments6 in front of experts.
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