obligatory parasite专性寄生虫;[生物] 专性寄生物
obligatory arbitration[法] 强制仲裁;翻译;强制仲裁
obligatory norm义务性规范;任务性规范
obligatory rule义务性规范;强制性规则
obligatory diapause专性滞育
obligatory renewal非硬性规定续约
obligatory jurisdiction强制管辖权;强制管辖英语
Obligatory Vessel义务船
obligatory requirement我们可以做出总结
ADJ（形容词） If something is obligatory, you must do it because of a rule or a law. 规定性的
Most women will be offered an ultrasound scan during pregnancy, although it's not obligatory.
大部分妇女怀孕期间都将进行超声波检查，尽管不是规定性的。