The word mandatory means all required.
This word means required. Example; Having health insurance will soon be mandatory for all Americans.
Education is mandatory in many countries.It is mandatory that you attend this meeting.
She was forced into mandatory (required) retirement.
A cooking course should be mandatory in schools
Attendance is mandatory means you have to go.
Yes.
You have to do it
optional
mandatory
The inclusion of raw data should not be considered mandatory.
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Overtime is mandatory at many factories.