笔走龙蛇

1. • the brush flows with the fluidity of a dragon or snake (idiom)

     lit.

2. • (of brushwork, esp for calligraphy) lively vigorous

     fig.

Character by character

• 笔(bǐ)writing brush
• 走(zǒu)walk
• 龙(lóng)surname Long
• 蛇(shé)snake