つけっぱなしじゃありませんでした
付けっぱなしじゃありませんでした
tsukeppanashijārimasendeshita

Noun
Desu Copula

The polite, past negative form of つけっぱなし

1. Was not left on.; Was not attached.; Was not left as is.

Past/Perfective
Negative
Polite
Terminal Form
Usually Written in Kana