Hello everybody! I've been learning Korean on my own so I have no one to ask this. I hope somebody can help me 
There's this thing I've been reading a lot. Certain syllables, like 현, 형, 석, when romanized, they have the eo replaced with u:
현 Hyeon / Hyun
형 Hyeong / Hyung
석 Seok / Suk
And there's also this one:
현대 Hyeondae / Hyundai ?
I wanted to know why this happened, because I don't have any clue
Thank you very much!
There's this thing I've been reading a lot. Certain syllables, like 현, 형, 석, when romanized, they have the eo replaced with u:
현 Hyeon / Hyun
형 Hyeong / Hyung
석 Seok / Suk
And there's also this one:
현대 Hyeondae / Hyundai ?
I wanted to know why this happened, because I don't have any clue