modality N4 common casualpolitewritten
なくては — must ~
なくては
Builds on なくて
Meaning
- must ~ / have to ~ — lit. 'if I don't ~, then (it's no good)', the consequence often left unspoken
Key sentence
もう行かなくては。
I have to get going now.
Formation
| Attaches to | Form | Example |
|---|---|---|
| verb (negative て-form) | V-なくて + は | 行かなくては / 返さなくては |
Examples
急がなくては、電車に間に合わない。
I have to hurry, or I won't make the train.
借りた本は明日までに返さなくては。
I have to return the book I borrowed by tomorrow.
約束は守らなくてはいけない。
You must keep your promises.
When you can't use it
- The trailing いけない／ならない ('no good') is usually dropped in speech: 行かなくては stands alone for 行かなくてはいけない. Spelling it out is just more explicit, not different in meaning.
Easily confused with
〜なくてはいけない 〜なくては is the trailed-off everyday form; 〜なくてはいけない completes the 'if not, no good.' Same obligation. なくちゃ なくちゃ is the casual contraction of なくては (て + は → ちゃ). Same meaning, more conversational. 〜ないと Both mean 'have to,' built on different conditionals: なくては (て-form + は) feels a touch more deliberate; ないと (と-conditional) is the breeziest.
See なくては in real sentences
Jengo shows なくては the way you actually meet it: inside real Japanese sentences, so it sticks instead of staying an abstract rule.
Study it in JengoSources Compiled with reference to A Dictionary of Advanced Japanese Grammar.