refined rosin

• 精制松香

refined rosin的用法和样例：

例句

1. The world gum rosin production appeares to decline in recent years.
   目前世界上脂松香生产在大多数国家出现下降趋势。
2. Shuxiang, Rosin I walked with an unforgettable childhood.
   书香，松香伴我走过了难忘的童年。