一、坚韧的英文是：
tough and tensile、firm and tenacious
二、短语搭配：
坚韧不拔firm and indomitable; persistent and dauntless; staunch and unyielding
质地坚韧be tensile
三、例句：
1、他的作品证明了他内心的坚韧。
His writings witness to an inner toughness.
2、坚韧不拔的史密斯坚持了整整八轮（比赛）。
The durable Smith lasted the full eight rounds.
3、坐在被告席上听候审判可使最坚韧的心失去勇气。
Sitting in the dock awaiting a sentence will unman the stoutest heart.
久美雍希
