水中 すいちゅう生物 せいぶつ観察 かんさつじゃなかったです
suichūseibutsukansatsujanakattadesu

Noun
Desu Copula

The polite, past negative form of 水中生物観察

1. Wasn't observing aquatic life.; Didn't observe aquatic life.

Past/Perfective
Negative
Polite
Casual Register