海洋 かいよう生物 せいぶつ がくじゃありませんでした
kaiyōseibutsuga kuja arimasendeshita

Noun
Desu Copula

The polite, past negative form of 海洋生物学

1. Was not marine biology.; Wasn't marine biology.

Past/Perfective
Negative
Polite
Terminal Form