perseverance
n[U]
continued steady effort to achieve an aim; steadfastness 坚持不懈; 不屈不挠
After months of disappointment, his perseverance was finally rewarded. 数月来他经历挫折而不断努力, 终於有了收获.
perseverance in the face of extreme hardship 面对极端困苦而百折不挠.
Though people have often laughed at stories told by seamen, it is now known that many of these 'monsters' which have at times been sighted are simply strange fish.