はまぐりじゃなかったです
蛤じゃなかったです
hamagurijanakattadesu

Noun
Desu Copula

The polite, past negative form of はまぐり

1. Wasn't a clam.; Wasn't saying "hm?" / Wasn't interjecting.

Past/Perfective
Negative
Polite
Casual Register
Usually Written in Kana