まいわしでわありませんでした
真鰯ではありませんでした
maiwashidewārimasendeshita

Noun
Desu Copula

The polite, past negative form of まいわし

1. Was not a true sardine.; Was not a genuine sardine.

Past/Perfective
Negative
Polite
Formal Register
Usually Written in Kana