1、Her unfailing determination led her to success.
她坚定不移的决心让她取得了成功。

2、His unfailing loyalty to his friends is admirable.
他对朋友们的忠诚无比值得赞赏。

3、The unfailing support from her family helped her through tough times.
家人对她的坚定支持帮助她度过了艰难时期。