ならない

Etymology
Negative form of.

Adjective

 * 1) illegal, forbidden, prohibited, not allowed (something that is not permitted to be done)
 * 2)  it’s bad if...,must not
 * 1) illegal, forbidden, prohibited, not allowed (something that is not permitted to be done)
 * 2)  it’s bad if...,must not

Usage notes

 * This sense is similar to . してはならないこと is something you’re not allowed to do, and してはいけないこと is something that you shouldn’t do because it brings about an unwanted result.