Хайх

ものではない

shouldn’t do something; it’s impossible to ~

JLPT

Бүтэц

V (root form)+ものではない
V (root form)+もんじゃない

Утга

「ものではない」is used to express something that according to common sense, proper behavior, or general norms, should not be done. It indirectly advises or gently warns the listener. The subject in the sentence is generally not specifically directed at the listener but is speaking in a general sense to everyone. It should not be used with superiors.
「もんじゃない」is often used in daily conversations.

目上めうえ

の

人ひと

にそんな

言い

い

方かた

をするものではない

。

You shouldn't say things like that to someone superior to you.

口くち

の