放射 ほうしゃ年代 ねんだいではありませんでした
hōshanendaidewārimasendeshita

Noun
Desu Copula

The polite, past negative form of 放射年代

1. Was not a radiometric date.; Was not a date obtained through radiometric dating.

Past/Perfective
Negative
Polite
Formal Register