lasting for a long time or difficult to get rid of

a persistent smell/skin rash 持续不散的气味／顽固的皮疹

Symptoms of the illness include a high temperature and a persistent dry cough. 病症包括高烧和持久的干咳。

There have been persistent rumours that the principal might take early retirement. 不断有谣言说校长可能会提前退休。

Someone who is persistent continues doing something or tries to do something in a determined but often unreasonable way.

Be persistent - don't give up. 要坚持不懈——别放弃。

He has been a persistent critic of the president. 他一贯对总统持批评态度。

She is a persistent offender and has been arrested five times this year for shoplifting. 她是个惯犯，今年已5次因在商店行窃被捕。