授業 じゅぎょう参観 さんかん じゃなかったです
jugyōsankanhijanakattadesu

Noun
Desu Copula

The polite, past negative form of 授業参観日

1. Wasn't a school visit day.; Wasn't the day for observing classes.

Past/Perfective
Negative
Polite
Casual Register