高速 こうそく自動 じどう しゃ国道 こくどうであれば
kōsokujidōshakokudōdeareba

Noun
Da Copula

The "-eba" conditional form ("if/when…") of 高速自動車国道

1. If it is a high-speed expressway; When it is a high-speed expressway

Ba Conditional