"Can I get a larger cup of coffee, please?"
Translation:Kan jeg få en større kopp kaffe, vær så snill?
i answered: kan jeg få en større kopp kaffe, takk? and it was wrong but it is what i hear around, vær så snill is too formal in this context. Actually I'm told that vær så snill is not much used anymore, except when children are too desperate to get candies