こうしかげろうじゃなかったです
紅糸蜻蛉じゃなかったです
kōshikagerōjanakattadesu

Noun
Desu Copula

The polite, past negative form of べにいととんぼ

1. Wasn't a red dragonfly.; Wasn't a red thread dragonfly.

Past/Perfective
Negative
Polite
Casual Register
Usually Written in Kana