びわこおうなまずじゃなかったです
琵琶湖大鯰じゃなかったです
biwako ō namazujanakattadesu

Noun
Desu Copula

The polite, past negative form of びわこおおなまず

1. Wasn't the great catfish of Lake Biwa.

Past/Perfective
Negative
Polite
Casual Register
Usually Written in Kana