What 반말 is, and who you can use it with
반말 ('half-speech') is the intimate, low register of Korean. You drop the polite -요 and use bare -아/-어 endings, plain past -았/었어, and questions with simple rising intonation. 밥 먹었어요? ('Did you eat?', polite) becomes 밥 먹었어? in 반말. The grammar is easier; the social rules are harder. Use 반말 only with: close friends of similar age, younger family, children, or someone who has explicitly said 말 놓으세요 ('please drop the formality'). Get this wrong and you sound rude.
Drop -요, keep the stem ending
Take any 해요체 (everyday polite) form and chop off the final -요: • 가요 ('go') → 가 ('go') • 먹어요 ('eat') → 먹어 • 봐요 ('see') → 봐 • 마셔요 ('drink') → 마셔 • 해요 ('do') → 해 Past tense follows the same rule: 갔어요 → 갔어, 먹었어요 → 먹었어, 했어요 → 했어.
The copula in 반말: -야 / -이야
In polite Korean, 친구예요 = 'is a friend'. In 반말 the copula -이에요/-예요 becomes -(이)야: • After a vowel: 친구야 ('is a friend') • After a consonant: 선생님이야 ('is a teacher') Question: just rising intonation, 친구야? ('a friend?'). Past stays regular: 친구였어 ('was a friend').
Questions, statements, commands
All four sentence types in 반말 look almost identical — intonation does the work: • Statement: 밥 먹어. ('I'm eating.') • Question: 밥 먹어? ('Are you eating?') • Command: 밥 먹어. ('Eat.', often spelled with strong tone) • Suggestion: 밥 먹자. ('Let's eat.', from -자) Propositive -자 ('let's') and -(으)ㄹ래? ('want to?') are very common in 반말 suggestions.
Pronouns and address
저 ('I', humble) flips to 나, and 저는 → 나는 or short 난. 저희 → 우리. You address peers by name + 야/아 (vocative): 민수야!, 지영아! (the -아 form follows a consonant batchim). Older family members keep their kinship terms: 엄마, 아빠, 형, 언니, 오빠, 누나 — these you can use casually, but the title comes first.
Who, when, never
Safe with: lifelong friends from school, your siblings (younger or sometimes same-age), your children, your romantic partner once you've agreed. Dangerous with: anyone older (even by a year), strangers, coworkers (default to polite), anyone you've just met. Rule of thumb for learners: don't switch to 반말 first. Wait for the older or higher-status person to invite you with 편하게 말해, 말 놓으세요, or simply use 반말 to you. Switching too early reads as 'this person doesn't know how Korean works' — which, fortunately, is forgiven for foreigners but worth getting right.
