臨界りんかい前核ぜんかく実験じっけんじゃありませんでした
rinkai zenkakujikkenjārimasendeshita

Noun
Desu Copula

The polite, past negative form of 臨界前核実験

1. Was not a critical pre-nuclear experiment.

Past/Perfective
Negative
Polite
Terminal Form