I'd like to add a bit more explanation. but I'm not very good in romanization, so I'll let it out ^^ 고맙습니다 = thank you (when you receive a gift, for example) 실례합니다 = excuse me (only when you are trying to get through some crowd murmuring "sorry.. pardon.. excuse me.. please let me through.." - not when you are asking to forgive you for something you have done wrong) 미안합니다 and 죄송합니다 = sorry (when you are asking forgiveness for something you have done; 죄송합니다 would be more formal and would mean that speaker considers his/her 'mistake' to be more serious and heavy comparing to situations when he/she would use 미안합니다)

미안합니다 Mianhabnida 죄송합니다 is more formal