GrammarJLPT N5
→ must
Must / Have to
JLPT N5Fixed phraseNeutral
なければならない is a standard Japanese expression used to convey obligation or necessity, equivalent to English "must" or "have to." It is formed by taking the negative form of a verb (ない-form), replacing ない with なければ (a conditional meaning "if not"), and then adding ならない ("it won't do" / "it is unacceptable"). The literal sense is therefore "if one does not do X, it won't do," which naturally produces the meaning of obligation. This expression is relatively formal and is common in both written and spoken Japanese. In casual speech, speakers frequently shorten it to なきゃ or use the similar but slightly less formal alternatives なくてはいけない, ないといけない, or the very casual なくちゃ. Compared to べき, which expresses a moral or logical "should," なければならない carries a stronger sense of unavoidable obligation or requirement. The grammar point can be used with verbs, and by extension with adjective and noun constructions via their negative forms, though the verb usage is by far the most common.
Examples
Example #1
明日は六時に起きなければならない。
Here なければならない expresses a personal obligation — the speaker has to get up early the next day. The ichidan verb 起きる drops its る to form the ない-stem 起き, and then なければならない is attached directly. This is a very natural and common way to talk about things you are required to do in daily life.I must wake up at six o'clock tomorrow.
Structures
- Verb
- Verb (ない-form, drop ない) + なければならない
- い-Adjective
- い-Adjective (drop い) + くなければならない
- な-Adjective / Noun
- な-Adjective / Noun + でなければならない
Common mistakes
A common error is incorrectly forming the ない-stem of godan verbs — for example, writing 飲むなければならない instead of the correct 飲まなければならない. Learners must remember to shift to the あ-column of the verb's consonant row before attaching なければならない. Another frequent mistake is confusing なければならない with なくてもいい (don't have to), which expresses the opposite meaning — lack of obligation. Additionally, some learners overuse the full なければならない in casual conversation where shorter forms like なきゃ or なくちゃ would sound much more natural; conversely, using the casual shortened forms in formal writing or speeches is inappropriate. Finally, learners sometimes mix up なければならない with べき; while both relate to obligation, べき suggests what one "should" do based on common sense or morality, whereas なければならない indicates a stronger, often unavoidable necessity.
Related
なくてはならないなくてはいけないなければいけないないといけないべきなくちゃ