n.代替,用处，好处,有帮助 v.对。。有用
They were impressed by his steadfast good cheer.
他整天笑呵呵的样子给他们留下很深的印象。
He remained steadfast in his determination to bring the killers to justice.
他要将杀人凶手绳之以法的决心一直没有动摇。
Her steadfast belief never left her for one moment.
她坚定的信仰从未动摇过.