せんうみつばめじゃありませんでした
潜海燕じゃありませんでした
sen'umitsubamejārimasendeshita

Noun
Desu Copula

The polite, past negative form of もぐりうみつばめ

1. Was not a hydrobatid.; Was not a storm petrel.

Past/Perfective
Negative
Polite
Terminal Form
Usually Written in Kana