/mænˈdəˌtɔri rul/ – Phrase
Definition: quy tắc bắt buộc.
A more thorough explanation: A mandatory rule is a legal requirement that must be followed or complied with, as opposed to being optional or discretionary. It is a rule that is binding and enforceable by law, and failure to adhere to it may result in legal consequences or penalties.
Example: The mandatory rule requires all employees to undergo safety training before starting their job.