博多はかた祇園ぎおん山笠やまかさであれば
hakatagion'yamakasadeareba

Noun
Da Copula

The "-eba" conditional form ("if/when…") of 博多祇園山笠

1. If it were Hakata Gion Yamakasa…; If the Hakata Gion Yamakasa were to happen…

Ba Conditional