persevering

a. 坚忍不拔的

A few persevering climbers finally reached the top.

少数几个攀登者坚忍不拔，终於登上了顶峰。

Refusing to give up or let go; persevering obstinately.

坚持不懈的，执意的拒绝放弃或听任的；顽固坚持的