How are these 3 different?
1.ものではない/もんじゃない
2.ない方がいい
3.べきではない
Is もんじゃない more casual and common in conversation? Do only girls use it?

Question

How are these 3 different?
1.ものではない/もんじゃない
2.ない方がいい
3.べきではない
Is もんじゃない more casual and common in conversation? Do only girls use it?

Answer

1... must not
2... doing ~~ is not good
3... shouldn't

1 is like warning
2 is soft or casual
3 is literary style, formal style

ものではない ... literary style, formal style
もんじゃない ... more casual and common in conversation, not only for girls, everyone use it.

Answer

ない方がいい - better translates to  " Not doing ～is good" 
Example- しない方がいい - "You shouldn't do it"   Literally -  The way (choice) of not doing ～is good

べきではない is stronger than ないほうがいい

Answers · 2

Still haven’t found your answers?

Don’t miss out on the opportunity to learn a language from the comfort of your own home. Browse our selection of experienced language tutors and enroll in your first lesson now!