上代 じょうだい東国 とうごく方言 ほうげんであれば
jōdaito ugoku hōgendeareba

Noun
Da Copula

The "-eba" conditional form ("if/when…") of 上代東国方言

1. If it were the ancient Tōkai dialect; If it were an old Tōkai dialect

Ba Conditional
Linguistics