People persist in leaving the tap running, which wastes water unnecessarily.

persist 是动词，由前缀 per-（表示"完全、彻底"）和词根 sist（来自拉丁语 sistere，意为"站立、保持"）组成，字面意思是"完全保持"，引申为"坚持、持续"的意思。