They had only recently arrived in London when tragedy struck - their son was killed in a traffic accident.

tragedy 来自希腊语 tragōidia，原指古希腊戏剧中的"悲剧"，现泛指"悲惨的事件"或"灾难"。这个词常用来描述导致巨大痛苦或损失的不幸事件，特别是涉及死亡或重大伤害的情况。