헐, 대박, 진짜?, 진짜요?, 말도 안 돼, 어떡해, 깜짝이야, 깜짝 놀랐어요, 설마, 세상에
Most variety show Korean starts with surprise: someone opens a box, falls in a pool or hears a result, and the cast react in one or two words. Today covers the common ones, 헐 (heol), 대박 (daebak), 진짜? (jinjja?), 말도 안 돼 (maldo an dwae) and 어떡해 (eotteokae), and which of them you could say to someone older. Nearly everything in this course is 반말, casual speech, because that is how the cast talk to each other, so each day says what is safe to copy and with whom.
Four words for 'no way'
All four turn up in almost any episode:
헐
heol
whoa, no way, ugh
Pure shock, most often at something bad or absurd. Fine with friends and online; said to a teacher, a boss or anyone older it sounds flippant, so don't.
대박
daebak
amazing, huge
Literally a 'big hit'. Usually good news, but it can mark something shockingly bad too, and the tone tells you which. Fine with friends and people your own age.
어떡해
eotteokae
oh no, what do I do
A squashed 어떻게 해 'how do (I) do it', said [어떠캐]. It is also what you say in sympathy when someone tells you bad news. 어떡해요 is safe with anyone.
설마
seolma
surely not, don't tell me
Said before the thing you fear is true: 설마 진짜? 'don't tell me it's real'. It is an ordinary adverb, not slang, so 설마요 is polite enough for anyone.
Why it works
A reaction is not a sentence, and Korean shows politeness in the ending of a sentence, so a one-word reaction has nowhere to put it. That leaves the choice of word to do the work. 설마 takes 요 easily and 대박 can become 대박이에요, but 헐 has no polite form in ordinary use, which is the clearest sign that it belongs among friends. When you are unsure, reach for a word that can carry 요.
One reaction, three levels
The casual column is what the cast say to each other:
Really?you can't quite believe it
Casual
진짜?
jinjja?
Polite
진짜요?
jinjjayo?
Formal
정말입니까?
jeongmarimnikka?
진짜 and 정말 both mean 'real, really'; 정말 is a shade more careful. The formal version sounds like a news interview, and on a variety show it is nearly always a joke about being stiff.
That makes no sensea claim you refuse to accept
Casual
말도 안 돼
maldo an dwae
Polite
말도 안 돼요
maldo an dwaeyo
Formal
말도 안 됩니다
maldo an doemnida
Word for word, 'it doesn't even work as words'. 돼 is 되다 'to work, to become' with its ending; the spelling 돼 against 되 trips up Koreans too.
What a frighta sudden noise or a hand on your shoulder
Casual
깜짝이야
kkamjjagiya
Polite
깜짝 놀랐어요
kkamjjak nollasseoyo
Formal
깜짝 놀랐습니다
kkamjjak nollatseumnida
깜짝 is the sound-picture of a sudden start. 깜짝이야 is blurted to nobody in particular; to make it polite you need a real verb, 놀랐어요 'I was startled'.
Why it works
The three columns differ only in the ending, which is the part Korean uses to show who is being spoken to. 깜짝이야 cannot simply take 요, because it is not really said to anyone, so the polite versions switch to a full sentence with a verb. The cast use the casual column because they are colleagues who perform being friends, and the show wants that closeness on screen. Copy the casual column with friends of your own age, and the middle one with everyone else.
Watching together
Two friends are watching a contestant cross a pool on stepping stones:
지은
헐, 저거 진짜야?
heol, jeogeo jinjjaya?
Whoa, is that real?
진짜 plus 야, the casual 'is it', makes the reaction a question. 저거 'that thing there' points at the screen.
민수
대박. 물에 빠졌어.
daebak. mure ppajyeosseo.
Amazing. He's fallen in the water.
지은
어떡해! 괜찮아?
eotteokae! gwaenchana?
Oh no! Is he all right?
Here 어떡해 is sympathy, not panic.
민수
괜찮아. 다 게임이야.
gwaenchana. da geimiya.
He's fine. It's all part of the game.
지은
설마 일부러?
seolma ilbureo?
Don't tell me he did it on purpose?
일부러 'on purpose'. After 설마 the sentence often just stops and the listener fills in the rest.
민수
말도 안 돼. 아, 또 빠졌어!
maldo an dwae. a, tto ppajyeosseo!
No way. Oh, he's fallen in again!
지은
세상에!
sesange!
Good grief!
세상에, literally 'in the world', is heard from every age group and is safe with anyone.
민수
아, 깜짝이야.
a, kkamjjagiya.
Argh, you made me jump.
Why it works
Every line here is 반말, because they are friends of the same age, and that is also how most of a variety show sounds. Notice how little of it is a full sentence: reactions are stacked, 말도 안 돼 then a short report, and the grammar lives in a few endings such as -야 and -어. When you listen, catch the reaction word first, because it tells you how to read everything after it.