daunt, 畏惧。-less, 不，没有。

1. Dauntless in spirit, they became steeled through hardship.

他们不屈不挠, 在艰苦的生活中锻炼得更加坚强了.

2. He is a dauntless aviator.

他是一位勇敢的飞行家;

3. The goal has now been finally attained through their dauntless and persistent efforts.

经过他们百折不挠,再接再励的努力,现在终于达到了目的.

4. Even though there are myriad hardships and hazards , they can't stop the dauntless explorers.

纵有千难万险, 也挡不住英勇的探险队员.

5. The dauntless entrepreneurs let their imagination fly in all directions.

这些无所畏惧的实业家,任自己的想象海阔天空,纵情翱翔.