adj.必须负担的(有责任的)
It's not a case of whether Enid wants to give evidence or not. If she overheard a criminal conversation, it's her bounden duty to report it to the police. 现在的问题不是伊妮德是否愿意作证。假如她偶然听到罪犯的谈话,那么,向警方报告是她义不容辞的责任。