you must be joking
- kiddingTeasing playfully
- seriousWeighty and requiring attention
- jokingSaying things in fun
- unbelievableImpossible to accept as true
- ridiculousInviting scorn through absurdity
surely · impossible · disbelief · sarcasm · incredulous · eyebrow · laughter · absurd · really · skeptical · shocked · stunned · pulling my leg · no way · are you serious · outrageous · scoff · mock
sincerity/seriousness
you must be jokingof course
Expression of obvious agreement
no kidding · naturally · that figures · obviously · fair enough