어야죠

we should, obviously — polite

Combines the have-to sense of 어야 with the of-course tone of 죠, so it means we really should, treating the obligation as something everyone already agrees on. 저도 줄여야죠 "I ought to cut back too", 군산 짬뽕 먹어야죠 "we've got to have Gunsan jjamppong". Said about the past it turns into a reproach for what someone failed to do: 선을 지키셨어야죠 "you should have kept your distance". Stems ending in a vowel take 야죠 instead (해야죠, 가야죠); the flat, neutral version is 어야 해요.

Register: polite spoken