沈水 ちんすい海岸 かいがんじゃなかったです
chinsuikaiganjanakattadesu

Noun
Desu Copula

The polite, past negative form of 沈水海岸

1. Wasn't a submerged coast.; Wasn't a coastline sinking into the water.

Past/Perfective
Negative
Polite
Casual Register