みず蒸気 じょうき改質 かいしつじゃありませんでした
mizu jōkika ishitsujārimasendeshita

Noun
Desu Copula

The polite, past negative form of 水蒸気改質

1. Was not steam reforming.; Wasn't steam reforming.

Past/Perfective
Negative
Polite
Terminal Form
Chemistry