这个自动浇水系统配备了精确的滴头来控制水流。

The automatic watering system is equipped with precise ___droppers to control water flow.

实验室里的滴管通常用来精确测量液体。

The ___droppers in the lab are usually used to measure liquids precisely.

警方正在追捕那些在街头活动的毒贩。

The police are chasing the ___dealers operating on the streets.