How to say since when in Korean;is it 언제부터? (correct) until when;언제까지?(correct) what about the Formal and Informal forms?(same) 엄마하고 아빠하고 누가 좋아해요? (엄마와 아빠 중에 누가 더 좋아요?) Which do you like more,your mother or father? [Is this sentence correct?] 누가 전화했어요? (누구한테 전화하는거니?, 존댓말: 누구한테 전화하시는거예요? ) what if I want to say "Whom are you calling?" Can I say 누가 이제 왔어요? instead of 이제 누가 왔어요? (It doesn't matter.) Can 지 않다 be used in the future tense? (can't be used. u can use 지 않을 것이다) While watching a Korean TV program someone was talking about something then said 질문이 있어요 and they translated it as "I don't think so" so is this correct? (wrong, 나는 그렇게 생각하지 않아. 질문 있어요 means any questions?)