がこうそうきんじゃありませんでした
鵞口瘡菌じゃありませんでした
gakōsōkinjārimasendeshita

Noun
Desu Copula

The polite, past negative form of がこうそうきん

1. Was not a canker sore bacterium.; Was not caused by canker sore bacteria.

Past/Perfective
Negative
Polite
Terminal Form
Usually Written in Kana