〜(な)くては〜ない

Pattern
〜(な)くては〜ない
Level
N4
Reading
〜(な)くては〜ない
Meaning
if not... not... (similar to 〜なければ〜ない)
Attaches to
くては-form of verb/adjective
Nuance & register

Often interchangeable with 〜なければ〜ない, but can sometimes carry a slightly stronger sense of obligation or necessity.

Example

今日中にやらなくてはならない。 I must do it by today.

More from Grammar Points