obligatory

adj.

必须的；应尽的；义务的；强制性的

obligatory right债权

obligatory course必修课

1. Attendance at school is obligatory.
   上学是强制性的。
2. 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。
3. Attendance at primary school is obligatory.
   上小学是义务的。

Obligatory Reduction of Ferric Chelates in Iron Uptake by Soybeans
The obligatory role of endothelial cells in the relaxation of arterial smooth muscle by acetylcholine
The non-obligatory role of endothelial cells in the relaxation of arterial smooth muscle by acetylcholine
Stress-free T-cell development: glucocorticoids are not obligatory
Haloanaerobiaceae : A New Family of Moderately Halophilic, Obligatory Anaerobic Bacteria
Disruption of the Jak1 gene demonstrates obligatory and nonredundant roles of the Jaks in cytokine-induced biologic responses.
The induction of ornithine decarboxylase as an early, possibly obligatory, event in mouse skin carcinogenesis
Proteolytic degradation of MAD3 (I kappa B alpha) and enhanced processing of the NF-kappa B precursor p105 are obligatory steps in t...
The interaction of a Ca2+-dependent monoclonal antibody with the protein C activation peptide region. Evidence for obligatory Ca2+ b...
Resting Respiratory Tract Dendritic Cells Preferentially Stimulate T Helper Cell Type 2 (Th2) Responses and Require Obligatory Cytok...