The old sweater served as a memento, reminding her of her college days.

memento 来自拉丁语，原意是"记住"。这个词由词根 mem（记忆）和名词后缀 -ento 组成，指"纪念品"或"能唤起回忆的物品"。在句中指那件旧毛衣作为唤起大学回忆的纪念物。