あれちねずみじゃなかったです
荒地鼠じゃなかったです
arechinezumijanakattadesu

Noun
Desu Copula

The polite, past negative form of あれちねずみ

1. Was not a field mouse.; Wasn't a field mouse.

Past/Perfective
Negative
Polite
Casual Register
Usually Written in Kana