sense of duty (obligation)
compulsory; obligatory; mandatory
making obligatory; making compulsory
compulsory military service
duty to support (a person)
duty of disclosure; duty to inform; obligation to notify
obligation to make a sincere effort (to follow a set of rules, etc.)
obligation of restitution
The Three Major Duties (education, work and payment of taxes)
compulsory school attendance
duty of commission; duty to act; obligation to act
carbon dioxide reducing obligation
obligation for a building site to have access to a public road wider than 4 meters
obligation to give notice