浮遊 ふゆう生物 せいぶつではありませんでした
fuyūseibutsudewārimasendeshita

Noun
Desu Copula

The polite, past negative form of 浮遊生物

1. Was not plankton.; Was not a planktonic organism.

Past/Perfective
Negative
Polite
Formal Register