tenacity

这张图片展现了生命的顽强。

This image shows the ___tenacity of life.

尽管面临重重困难，他的坚韧最终帮助他完成了这个项目。

Despite many obstacles, his ___tenacity finally helped him complete the project.

登山绳的韧性确保了它在极端条件下也不会断裂。

The ___tenacity of the climbing rope ensures it won't break under extreme conditions.