necessary; needed; essential; necessity; need; requirement
interrogative sentence-ending particle expressing doubt
secrecy; highly classified information
treatment; service; handling (of a machine, tool, etc.); operation; treating as; treating like
to be able (to); to be possible (to)
he; she; that person; (arch.) you
offender; criminal; culprit
to hear; to listen (e.g. to music); to ask; to enquire; to hear about; to hear of; to follow (advice, order, etc.)