a discreet passageway的用法和样例：
- It was a discreet apartment in a quiet street.
- In Kata, a discreet hair clip is permitted.
- From that moment the debate was lost. Churchill sat up, gloating at his critics with a discreet twinkle, like a cat presented with an unexpectedly large bowl of cream.
- They separated at her doorstep with a discreet handshake.