to display one's slight skill before an expert (idiom)
班 · 10 strokes
Depicts a knife (刂) cutting a gem into two halves (玨), based on the original meaning "to divide". The meaning later shifted to "division", "group", and "team".
门 · 3 strokes
Simplified form of 門. Pictograph of a gate.
弄 · 7 strokes
Depicts a pair of hands (廾) playing with a jade object (玉).
斧 · 8 strokes
Phonosemantic compound. 斤 represents the meaning and 父 represents the sound.
在你面前谈书法,我真是班门弄斧了。
Discussing calligraphy in front of you — I'm really showing off in front of an expert.