Kings and queens in the past had the power to execute those who opposed them.

execute 是动词，由前缀 ex-（表示"向外"或"彻底"）和词根 secut（来自拉丁语 sequi，意为"跟随"）组成，原意是"彻底跟随到底"。在现代英语中，execute 的主要含义是"执行、实施"，特指"执行死刑"，即"处决"。