The children's constant noise completely exasperated the father who was trying to work.

exasperated 是动词 exasperate 的过去式。exasperate 由前缀 ex-（表示"完全、彻底"）和 asper（拉丁词根，意为"粗糙、困难"）组成，字面意思是"使事情变得完全困难"，引申为"激怒、使恼怒"的意思。exasperated 在这里表示"被彻底惹恼"的状态。