obligevt.迫使;责成;使感激;施恩于;帮 ... 的忙;使…成为必要vi.帮忙
obligationn.义务;责任
obligatory onadj.应尽的(不可推卸的)
obligatory rule强制性规则
obligatory bond[经] 强制性的债券
obligatory term义务年限
obligatory gene必定基因, 专性基因
obligatory norms义务性规范
obligatory audit[经] 强制审计
"attendance is obligatory"
"an obligatory contribution"
"he made all the obligatory apologies"