obligatoryadj.强制性的；义务的；必须的obligatory self-insurance固定自保部分obligatory presentation copy纳本obligatory parasitic bacteria专性寄生菌obligatory anaerobic bacteria专性嫌气细菌obligatory water reabsorption被动性水重吸收obligatory eccentric fixation强迫性偏注视obligatory character provision强制性规定obligatory judicial settlement强制司法解决obligatory aerobic respiration专性有氧呼吸obligatory annual contribution每年度必须交纳的会费