ㄴ다고

Echoing an action back in disbelief

Throws an action back at the person who said it, almost always in disbelief: 'You don't know this?', 'We have to?', 'You have to eat this in Taiwan?'. Six of these eight lines are exactly that kind of incredulous echo. Without the question it can instead insist on something you already stated. It attaches to present-tense action verbs after a vowel; 는다고 is the same after a consonant, and 다고 handles descriptions.

Register: casual; add 요 for polite