There was a man standing outside the door with an axe, and there was a class word on the door, which

Show amateur skills in front of an expert.

Explanation]: Dance the axe in front of Luban's gate. The metaphor is to show off his skills in front of the connoisseurs, and he does not measure himself.

From]: Tang Liu Zongyuan's "Wang's Bozhong Singing and Poem Preface": "Operate the axe in the ban, the gate of Ying, Siqiang Yan'er." "Song Ouyang Xiu's "Book with Mei Shengyu": "Yesterday in Zhending, there were seven or eight poems, and today they are recorded, and the class has an axe, which is ridiculous and ridiculous." ”