1. (in the first person) expressing the future tense.
this time next week I shall be in Scotland
2. expressing a strong assertion or intention.
they shall succeed
3. expressing an instruction or command.
you shall not steal
4. used in questions indicating offers or suggestions.
shall I send you the book?
shall mandatory = ist obligatorisch
mandatory = required by law or rules; compulsory.
wearing helmets was made mandatory for cyclists
must mandatary = muss zwingend sein
must mandatory = muss verpflichtend sein
compulsory = verpflichtend. Required by law or a rule; obligatory. Compulsory military service