Japanese from zero · N2 Lesson 33

Ai's rules

〜ねばならない・〜てはならない・〜ものではない・〜ずに済む/〜なくて済む・〜なくもない

In this lesson, you will learn to say what must be done in a stiff, formal way with 〜ねばならない, what must never be done with 〜てはならない, what a sensible person doesn't do with 〜ものではない, that you are spared something with 〜ずに済む and 〜なくて済む, and to give a modest yes with 〜なくもない. It is the week before Lisa's final interview, and Ai comes to dinner with a list of rules.

By the end you will be able to say

面接の日は早く行かねばならない。On the day of the interview, I must go early.

人の悪口を言ってはならない。You must never speak badly of others.

答えは丸暗記するものではない。Answers aren't something to learn by heart.

今準備すれば、当日慌てずに済む。If I prepare now, I won't have to panic on the day.

自信がなくもない。It's not that I have no confidence.

The grammar in this lesson

〜ねばならない — must (formal, written) — 〜ねばならない is a stiff, written way to say 〜なければならない (must).
〜てはならない — must not — A て-form + はならない forbids something firmly, as a rule with no exceptions.
〜ものではない — one shouldn't; it's not something one does — A dictionary-form verb + ものではない gives common-sense advice: what a sensible person doesn't do.
〜ずに済む / 〜なくて済む — get by without; be spared (doing) — 〜ずに済む and 〜なくて済む say you are spared something you thought you would have to do.
〜なくもない / 〜なくはない — it's not that ... not; a little, maybe — A double negative that gives a modest yes: 自信がなくもない (I have some confidence).