After the earthquake, the city's power system was completely disrupted.

disrupted 是动词 disrupt 的过去分词形式，在句中表示被动。disrupt 由前缀 dis-（表示"分离、破坏"）和词根 rupt（来自拉丁语 rumpere，意为"打破"）组成，意思是"使中断、扰乱"。disrupted 表示"被破坏、被打乱"的状态。