VERB + -(으)ㄴ/는데 connects two mildly contradicting things or when there is a notable/surprising coincidence. - 아직 4월인데 벌써 덥다 = It is only April and it's already hot. (contradiction) - 집을 나오는데 비가 갑자기 쏟아졌다. As I was leaving home, there was a sudden downpour. (unexpected incident) The verb form can vary depending on what comes before it. 1. 길을 가는데 ... => -는데 after a verb. 2. 날씨가 맑은데 ... >= -(으)ㄴ데 after an adjective. 3. 내가 일등인데 ... >= -인데 after a noun: 처음(n)이다 + -ㄴ데 -> 처음인데 = (it) is. 4. 그 말이 아닌데 ... >= X-이/가 아니다 + -ㄴ데 -> 아닌데 (it) is not. 아니다 is the opposite of 이다. #3 is a special case of #1 where the verb is 이다, a special verb that couples two things, as in "A is B". e.g. 내가 일등이다 (I am the first) => 내가 일등인데 애들은 아니라고 한다 (I am the first one but my friends say I'me not). -(으)ㄴ/는데/인데 can sometimes come at the end of a sentence if the second part of the phrase is already known through the context. This is used a lot in song lyrics because it leaves a nuance rather than resolving everything.

(To be continued) 4. Expecting an answer or a response A: 지금 저랑 같이 갈래요? Do you want to go with me now? B: 지금요? 지금 바쁜데요... Right now? I'm busy, though... A: 뭐해요? What are you doing? B: 저 집에 쉬고 있는데요 Well, I am resting at home. 5. Showing surprise or exclamation 멋있는데(는데요)! Oh that's cool! 참 맛있는데(는데요)! Wow, this is delicious! How delicious this is!

는데 with an action verb (eat, 먹다 - 먹는데 - 먹었는데 / sleep, 자다 - 자는데 - 잤는데 / study, 공부하다 - 공부하는데 - 공부했는데 / drink, 마시다 - 마시는데 - 마셨는데) -은데 with a regular descriptive verb (be good, 좋다 - 좋은데 - 좋았는데 / be small, 작다 - 작은데 - 작았는데 / be much, 많다 - 많은데 - 많았는데 / be narrow, 좁다 - 좁은데 - 좁았는데) -ㄴ는데 with an irregular descriptive verb (be pretty, 예쁘다 - 예쁜데 - 예뻤는데 / be cold, 춥다 - 추운데 - 추웠는데 / be far, 멀다 - 먼데 - 멀었는데 / be big, 크다 - 큰데 - 컸는데 / be long, 길다 - 긴데 - 길었는데) 1. Contrast : but, however, although 저는 수학을 잘하는데 제 동생은 수학을 잘 못해요. I am good at math, but my sister(brother) is not good at math. 미국은 땅이 넓은데 한국은 땅이 좁아요. The U.S. is big, but Korea is small. 어제는 커피를 마셨는데 오늘은 커피를 안 마셨어요. I drank coffee yesterday, but today I didn’t drink. 어제는 따뜻했는데 오늘은 좀 쌀쌀해요. It was warm yesterday, however it is chilly today. 매일 공부하는데 계속 잊어버려요. Although I study every, I keep forgetting it. 작년에는 비가 많이 왔는데 올해는 비가 거의 안 와요. It rained a lot last year, but it hardly rain this year. 옛날에는 공기가 좋았는데 지금은 아주 안 좋아요. The air was very clean in the past, but it is very bad now. 이 스마트폰은 비싼데 안 좋아요. This smart phone is very expensive, but it is not good. 2. Explaining the background or the situation before making a suggestion, a request, or a question 비가 오는데 어디에 가세요? It is raining, where are you going? 이렇게 늦었는데 아직도 일을 하세요? It is very late, are you still working? 돈도 없는데 이렇게 비싼 가방을 어디에서 샀어요? We don’t have money, where did you get this expensive bag? 오늘 좀 바쁜데 내일 만날까요? I am a little bit busy today, can we meet tomorrow? 오늘 날씨가 안 좋은데 내일 떠나는 게 어때요? The weather is not good today, how about we leave tomorrow? 3. Explaining the situation before explaining what happened 어제 자고 있었는데 한국에서 전화가 왔어요. I was sleeping yesterday, then I got a phone call from Korea. 오늘 학교에 갔는데 아무도 없었어요 Today I went to school and nobody was there. (To be continued)

Come to think of it, there is another -데 ending (with no -(으)ㄴ/는 before it) which is unrelated. This ending just relates what one has seen recently like in passing. And it is less common than the other one. - 아까 보니까 영철이는 집에 가데 = I saw 영철 going home a while back.