保証 ほしょう牛乳 ぎゅうにゅうではありませんでした
hoshōgyūnyūdewārimasendeshita

Noun
Desu Copula

The polite, past negative form of 保証牛乳

1. Was not guaranteed milk.; Was not assured milk.

Past/Perfective
Negative
Polite
Formal Register