おうかじゃなかったです
大蚊じゃなかったです
ōkajanakattadesu

Noun
Desu Copula

The polite, past negative form of ががんぼ

1. Wasn't a large mosquito.; Wasn't a big mosquito.

Past/Perfective
Negative
Polite
Casual Register
Usually Written in Kana