???? & ?????? ???????? ???????? ???? ?? ??? ?? ???? ?? ????????????? ???? ???? ???? ???? ???, ???? ???? ???? ???? ???? ???? ???? ???? ???? ???If a grammatical basic principle that is definitely extra to ????is often a vowel ??and there is no other option in addition to a vowel ??then that grammatical principle can not be additional Cheonan???? to ?