かく分裂 ぶんれつ生成 せいせい ぶつではありませんでした
kakubunretsu sei seibutsudewārimasendeshita

Noun
Desu Copula

The polite, past negative form of 核分裂生成物

1. Was not a fission product.; Was not a nuclear fission product.

Past/Perfective
Negative
Polite
Formal Register