She knew the velvet dress was being ruined 中为什么要加being
问题描述：
She knew the velvet dress was being ruined 中为什么要加being
而不是She knew the velvet dress was ruined
答
was being ruined 这是过去进行时被动语态,表示的动作和主句的动作同时发生.
was ruined是一般过去时被动语态,只表示过去的动作.用在此处不是很恰当.
句意:她知道那件 丝绒礼服正遭到损毁.