"attendance is obligatory"
"an obligatory contribution"
required by obligation or compulsion or convention;
"he made all the obligatory apologies"
双语例句
用作形容词 (adj.)
Attendance at school is obligatory. 上学是强制性的。
It is an obligatory step that does not arise from revenge, rancour or other lower emotions, but from the rational necessity to make mankind gain insight. 这是一个强制性的步骤，不产生报复，怨恨或其他低的情感，但是从理性的必要性，使人类了解。
Attendance at primary school is obligatory. 上小学是义务的。
