supererogatory

adj.额外的,超出职务的

超常的；超出应尽之责的

形容词

1、He went above and beyond the call of duty, performing supererogatory tasks without hesitation.
他超乎职责，毫不犹豫地完成了超出应尽之责的任务。
2、The extra effort he put into organizing the event was truly supererogatory.
他在组织活动上的额外努力确实超出寻常。