tenacious

她以顽强的意志坚持完成了马拉松比赛。

She finished the marathon with ___tenacious determination.

那株坚韧的藤蔓紧紧缠绕在排水管上，谁也扯不下来。

The ___tenacious vine had wrapped itself so tightly around the drainpipe that no one could pull it free.

那位坚持不懈的侦探花了十六年反复重启悬案调查，终于找到了那名失踪的证人。

The ___tenacious detective spent sixteen years reopening the cold case until he finally located the missing witness.