〜なくては いけません

Meaning

This grammar pattern expresses that something must be done or is necessary to do. It has the same meaning as 動詞（ない形）なければなりません and indicates an obligation or something that cannot be avoided, even if unwilling. The negative verb form is combined with なくては いけません to create this obligatory meaning.

Formation

Examples

1. 海外に 行く時は、パスポートを 持たなくては いけません。
   When traveling abroad, you must have a passport.

2. このDVDは 金曜日までに 返さなくては いけません。
   This DVD must be returned by Friday.

3. 日本語会話の 練習なので、みなさんは 日本語で 話さなくては いけないよ。
   Since this is a Japanese conversation practice, everyone must speak in Japanese.

4. 会議が 始まると 休めないから、今から ランチを 食べなくちゃ（いけない）。
   Since we won't be able to take a break once the meeting starts, I must eat lunch now.

Summary

• Formation: Negative verb base (without ない) + なくては いけません
• Common casual variations include なくてはいけない, なくちゃいけない, and simply なくちゃ
• Expresses unavoidable obligation or necessity, often implying reluctance or circumstances forcing the action