dropped by drop

• adv. 一滴一滴地(一点一点地)

dropped by drop的用法和样例：

例句

1. A can for oil, especially a can with a spout constructed to release oil drop by drop, as for lubricating machinery.
   油罐盛油的罐，特别是指安着可一滴一滴地滴油的喷嘴的油罐，用以润滑机器