chip away：v. 一点点削弱；逐渐损害。chip away at：削弱; 损害。

【例句】

It will be necessary to chip away all the paint before applying a new layer.
涂新漆以前，必须把原来的漆全铲掉。

All her life, little by little, he's tried to chip away at her hopes!
在她一生中，他一直企图一点一点地使她的希望破灭。