one and only

形容词 one and only:

1. eminent beyond or above comparison
   同义词：matchless, nonpareil, one, peerless, unmatched, unmatchable, unrivaled, unrivalled

1. She is my one and only friend.
   她是我惟一的朋友。
2. The one and only way to rescuer him is to lower down a rope.
   营救他的唯一办法是往下放一根绳索。
3. He is my one and only friend.
   他是我唯一的朋友。