영어공부 게시판

Come again?  (meaning "미안합니다. 다시 한번 말씀 해 주세요.")

Other ways:
(a very polite way) “Can you please repeat that?” or “Can you say that again? I didn't hear you clearly the first time.”
or {"Pardon me.",  "Excuse me.", "What?", "I beg your pardon?", "Run that by me again?", "Again?", "Huh?", "You what?"}