ㄴ데요

Polite reaction: 'oh, it's quite...'

Ends a line politely with a reaction you are having right now, usually to something just tasted, seen or touched: it's so crispy, this has a nice kick, that's a bit pricey, the chocolate tastes a bit weird. The 데 leaves a slight hang on the end, so it sounds like an impression offered rather than a fact declared, which is how it carries mild surprise or a soft complaint. 네요 also reacts, but flatly; ㄴ데요 keeps something in reserve.

Register: polite, conversational