He has been campaigning for better highway safety for years - you have to admire his persistence.

persistence 是名词，由动词 persist（坚持）加上名词后缀 -ence 构成。persist 本身由前缀 per-（表示“完全、彻底”）和词根 sist（来自拉丁语 sistere，意为“站立”）组成，字面意思是“完全站立不动”，引申为“坚持、持续”。 persistence 指“坚持不懈、持续不断”的品质或行为。