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Are there any differences of nuance between "You must be joking!" and "You've gotta be joking!"? Thanks in advance:)
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aramahosiAre there any differences of nuance between "You must be joking!" and "You've gotta be joking!"?
The difference is register. The first is more "proper". The second is closer to slang and includes a non-word 'gotta', which is really 'got to'.

CJ
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I'd say the second one is more colloquial...
 CalifJim's reply was promoted to an answer.