1.

1. 不倦：unwearied /疲倦的/不累的/孜孜不倦的/ | unwearying /不倦/ | unweathered /未风化的/未经风化的/

1. showing sustained enthusiastic action with unflagging vitality

    e.g. an indefatigable advocate of equal rights
           a tireless worker
           unflagging pursuit of excellence

    Synonym: indefatigabletirelessunflagging