造句子，既含同位语，又含非限制性定语从句

I have no idea how his parents were sad on hearing that their son was killed in the earthquake. 我不知道他的父母一听到他在地震中阵亡是多么悲伤！(同位语从句)二、从句作用的不同。定语从句具有形容词的特点，对先行词起修饰、限定作用，描述先行词的性质或特征，与先行词之间是所属关系。