南海 なんかいトラフ巨大 きょだい地震 じしんだったら
nankaitorafu kyodai jishindattara

Noun
Da Copula

The "-tara" conditional form ("if/when…") of 南海トラフ巨大地震

1. If/When the Nankai Trough mega-earthquake happens; If/When there were to be a Nankai Trough mega-earthquake

Tara Conditional