せんうみつばめでわありませんでした
潜海燕ではありませんでした
sen'umitsubamedewārimasendeshita

Noun
Desu Copula

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

1. Was not a sea swallow.; Was not a petrel.

Past/Perfective
Negative
Polite
Formal Register
Usually Written in Kana