vt.& vi.执行; 履行; 表演; 扮演 vt.工作; 做; 进行; 完成 vi.运行,表现; (驯兽)玩把戏 1. The UN must perform a delicate balancing act between the different sides in the conflict. 联合国必须在冲突各方之间担任公正的协调工作。 2. It is the obligation of citizens to perform military service. 服兵役是每个公民的义务。