“junkyard dog”别理解成“废品堆放场的狗”，其正确的含义是讨厌、恶毒、野蛮的人或狗。

【例句】
Though he's always polite when he's in public, Tiffany's husband is meaner than a junkyard dog behind closed doors.
虽然他在公共场合总是彬彬有礼，但蒂芙尼的丈夫在关起门来却是一个野蛮的人。

He is a man meaner than a junkyard dog. He likes to take advantage of others.
他是一个讨厌的男人。他喜欢占别人的便宜。