1、She worked indefatigably and enthusiastically to interest the young in music.
為了激發(fā)年輕人對音樂的興趣，她一直孜孜不倦、積極熱情地工作。

2、She seemed gentle, yet indefatigably determined to survive.
她看上很溫和，卻不屈不饒地對抗生存問題。

3、He always applies himself wholeheartedly and indefatigably to the tasks given him.
給他的任務(wù)他總是全心全意不屈不撓地去完成。