Day 28: Joining sentences
Your grammar is finished. What separates you from a Korean speaker now is length — you speak in short correct sentences, and Koreans speak in long ones.
밥 먹었어요. 그리고 영화 봤어요. → 밥 먹고 영화 봤어요.
Five connectors today. ★ The last one, -는데, is the single most-used ending in spoken Korean, and almost no course teaches it early enough.
1. -고 — "and"
### stem + 고 — lists actions or facts in order
| 밥 먹고 영화 봤어요. | I ate and watched a film |
|---|---|
| 저는 학생이고, 친구는 회사원이에요. | I'm a student and my friend works |
| 싸고 맛있어요. | It's cheap and tasty |
★ -고 does not change for tense. The last verb carries it: 밥 먹고 영화 봤어요 — 먹고 stays plain, and 봤어요 makes the whole thing past.
2. ★★ -아/어서 vs -(으)니까 — two "because"s
Both mean because / so. The difference decides which one you can use.
| Form | Use | |
|---|---|---|
| -아/어서 | 해요 form − 요 + 서 | ★ cause and effect, stating something |
| -(으)니까 | vowel → -니까, batchim → -으니까 | ★ giving a reason for a request or suggestion |
| 배고파서 밥 먹었어요. | I was hungry, so I ate |
|---|---|
| 비가 와서 못 갔어요. | It rained, so I couldn't go |
| 바쁘니까 나중에 전화할게요. | I'm busy, so I'll call later |
| 추우니까 문 닫으세요. | It's cold, so close the door |
⚠️ The rule that actually matters
### -아/어서 CANNOT be followed by a command, a request or a suggestion.
| ❌ | ✅ |
|---|---|
| 추우니까 문 닫으세요 | |
| 바쁘니까 나중에 갈까요? |
★ If the second half is 세요, 주세요, -ㄹ까요 or -ㄹ게요 — you must use 니까. Otherwise 서 is the more common and neutral choice.
⚠️ And -아/어서 never carries tense either — 배고팠어서 is wrong. 배고파서, with the past only on the final verb. (니까 can take it: 배고팠으니까.)
★ Two you already know: 그래서 (so, therefore) and 그러니까 (so, in that case) are these same endings turned into sentence openers.
3. -지만 — "but"
### stem + 지만
| 어렵지만 재미있어요. | It's hard but fun |
|---|---|
| 비싸지만 맛있어요. | It's expensive but tasty |
| 가고 싶지만 시간이 없어요. | I want to go but I have no time |
★ -지만 takes tense freely — 갔지만, 좋았지만. Unlike 서, it has no restrictions. Sentence-opener version: 하지만 / 그렇지만.
4. ★★ -는데 — the one Koreans actually use
-는데 is the most frequent connector in spoken Korean, and it does not translate cleanly. It means roughly "and… / but… / so here's the situation…" — it sets up background for what comes next.
### Action verbs → -는데 · Descriptive verbs → -(으)ㄴ데 · Past → -았/었는데
| 한국어 공부하는데 어려워요. | I'm studying Korean and it's hard |
|---|---|
| 비싼데 살까요? | It's expensive — shall we buy it anyway? |
| 어제 갔는데 문 닫았어요. | I went yesterday but it was closed |
| 친구를 만났는데 정말 반가웠어요. | I met a friend and it was so nice |
★ Four jobs, one ending:
| Job | Example |
|---|---|
| contrast (but) | 좋은데 비싸요 |
| background (and so) | 시간 없는데 다음에 봐요 |
| softening a request | 저기, 부탁이 있는데요… |
| trailing off politely | — 어디 가요? — 친구 만나는데요… |
⚠️ ★ -는데요 on its own, trailing off, is extremely common and very polite. It leaves the sentence open for the listener to respond, and it is how Koreans soften almost everything. 저 지금 좀 바쁜데요… says "I'm a bit busy right now" far more gently than 바빠요.
★ If you learn one thing from today, make it this: end a hesitant sentence with -는데요 instead of stopping flat. It changes how you come across more than any vocabulary will.
5. -(으)면 and -(으)ㄹ 때 — if and when
| -(으)면 | if, when | 시간 있으면 전화하세요. — Call if you have time |
|---|---|---|
| -(으)ㄹ 때 | when, while | 밥 먹을 때 물 마셔요. — I drink water when I eat |
(You met -(으)면 inside -(으)면 안 돼요 on Day 20.)
한국에 가면 연락할게요. — I'll get in touch when I go to Korea.어릴 때 캐나다에 살았어요. — I lived in Canada when I was young.
6. Sentence openers, and reactions
Openers
| 그리고 | and |
|---|---|
| 그래서 | so, therefore |
| 그런데 / 근데 | ★ but, by the way — 근데 is what people say |
| 하지만 | however |
| 그러니까 | so, in other words |
| 그럼 | then, in that case |
★ Reactions — say something back
| 아, 네. | ah, right |
|---|---|
| 그래요? | really? |
| 진짜요? / 정말요? | seriously? |
| 맞아요. | that's right |
| 그렇구나. / 그렇군요. | ★ ah, I see |
| 그러네요. | you're right, actually |
| 좋겠다! | ★ lucky you! |
| 아이고… | oh dear |
| 어떡해요! | oh no, what will you do! |
★ Korean conversation expects constant noise back — 네, 네, 아 그래요?, 맞아요 — and silence reads as incomprehension or disagreement (Day 3 §5). 그렇구나 and 좋겠다 are the two to add today.
Buying time
음… · 글쎄요… (hmm, not sure) · 뭐지… (what's it called) · 잠깐만요 (hang on) · 어떻게 말하지… (how do I say this)
7. Dialogue — the same content, twice
A — correct, and nothing like real speech
민수: 주말에 뭐 했어요?Alex: 부산에 갔어요. 좋았어요. 비쌌어요.민수: 그래요.
B — the same facts, with today's endings
민수: 주말에 뭐 했어요?Alex: 아, 부산에 갔는데요, 진짜 좋았어요.민수: 오, 좋겠다! 어떻게 갔어요?Alex: KTX 타고 갔어요. 빠른데 좀 비쌌어요.민수: 그렇구나. 뭐 했어요?Alex: 바다 보고 회 먹었어요. 처음 먹어 봤는데 괜찮았어요.민수: 진짜요? 저는 회 못 먹는데…Alex: 아, 그래요? 저도 무서웠는데 맛있었어요.민수: 그럼 다음에 같이 가요. 시간 있으면요.Alex: 좋아요! 근데 좀 머니까 아침 일찍 가야 돼요.민수: 그러네요. 그럼 토요일 어때요?
★ Version B has no grammar you did not have on Day 27. Every difference is a connector or a reaction — -는데, -고, -니까, -면, 그렇구나, 좋겠다, 진짜요.★ That is the entire gap between correct Korean and real Korean, and you just closed it.
8. Exercises
A. Join with -고.
- 밥 먹었어요. 영화 봤어요.
- 싸요. 맛있어요.
B. ⚠️★ -아/어서 or -(으)니까?
- 배고___ 밥 먹었어요.
- 추우___ 문 닫으세요.
- 비가 와___ 못 갔어요.
- 바쁘___ 나중에 전화할게요.
C. Join with -지만.
- 어려워요. 재미있어요.
- 비싸요. 맛있어요.
D. ★ -는데 / -(으)ㄴ데 / -았는데.
- 공부하다 (present, action) 2. 비싸다 (descriptive) 3. 가다 (past) 4. 시간 없다
E. -(으)면 or -(으)ㄹ 때?
- Call if you have time.
- I drink water when I eat.
- I lived in Canada when I was young.
F. React.
- Your friend went to Busan. 2. You've just understood something.
- You're not sure. 4. Something bad happened to them.
G. ⚠️ Fix the mistake.
- 추워서 문 닫으세요.
- 배고팠어서 밥 먹었어요.
- 비싼는데 살까요?
- (hesitating) 저 지금 바빠요.
Answers
A. 1. 밥 먹고 영화 봤어요. 2. 싸고 맛있어요. B. 1. 배고파서 2. 추우니까 (command follows) 3. 비가 와서 4. 바쁘니까 (-ㄹ게요 follows) C. 1. 어렵지만 재미있어요. 2. 비싸지만 맛있어요. D. 1. 공부하는데 2. 비싼데 3. 갔는데 4. 시간 없는데 (있다/없다 → 는데) E. 1. 시간 있으면 전화하세요. 2. 밥 먹을 때 물 마셔요. 3. 어릴 때 캐나다에 살았어요. F. 1. 좋겠다! 2. 그렇구나. 3. 글쎄요… 4. 어떡해요! / 아이고… G. 1. 추우니까 — a command follows 2. 배고파서 — 서 takes no tense 3. 비싼데 4. 좀 바쁜데요… — far gentler
9. Today's 10 sentences (flashcards)
- 밥 먹고 영화 봤어요. — I ate and watched a film
- 배고파서 밥 먹었어요. — I was hungry so I ate
- 바쁘니까 나중에 전화할게요. — I'm busy so I'll call later
- 어렵지만 재미있어요. — It's hard but fun
- 어제 갔는데 문 닫았어요. — I went yesterday but it was closed
- 저 지금 좀 바쁜데요… — I'm a bit busy right now…
- 시간 있으면 전화하세요. — Call if you have time
- 그렇구나. — Ah, I see
- 좋겠다! — Lucky you!
- 글쎄요… — Hmm, I'm not sure
10. 📲 Upload to LangNote
Upload both versions of the dialogue (section 7) and section 9 → study language Korean.
| Mission | What to do with it today |
|---|---|
| 🎧 Podcast | Today's key mission. Play A and B back to back — hearing the gap is the lesson |
| ✍️ Dictation | -는데 is unstressed and fast; you will miss it entirely at first |
| 🗣 Shadowing | Version B, both roles, matching the melody |
| 🎭 Role-play | Talk for five turns using -는데, -니까 and 그렇구나 at least once each |
| 📖 Vocab | ★ -아/어서 / -(으)니까 as one card with the rule, so they never separate |
★ Tomorrow is conversation day — no new material, thirty minutes of talking.Day 30 re-records your Day 1 sentences. Find that recording tonight.
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