Translation guide
Expresses obligation or necessity. In Japanese, this is most commonly conveyed using the pattern 'must do' or 'have to do', formed by the negative conditional of a verb plus ならない/いけない, or by the double-negative なくては/なければ plus ならない/いけない. There are also shorter casual forms and other expressions for 'need to' or 'should'.
Expressing that something is required or must be done, often due to rules, duty, or circumstances.
Standard formal pattern meaning 'must do' or 'have to do'. Used in writing and formal speech. V is the negative stem (ない-form without ない).
I have to submit the report by tomorrow.
Similar to なければならない, but slightly more subjective, often implying personal obligation or that it's bad if you don't. Very common in spoken Japanese.
I have to go now.
Equivalent to なければいけない, but slightly more colloquial. Often contracted to なくちゃいけない in casual speech.
I have to study every day.
Formal pattern similar to なければならない, but slightly less common. Used in writing and formal contexts.
We have to follow the rules.
Casual contraction of なければ, often used without いけない/ならない in informal speech. Can sound abrupt or friendly depending on context.
I gotta wake up early.
Expressing that something is necessary, often for a purpose or to achieve a goal.
Literally 'there is a need to V'. More formal and objective than なければならない. Used in written and spoken Japanese.
I need to practice more.
Colloquial pattern meaning 'must' or 'have to'. Often used in spoken Japanese. Can be shortened to ないと in casual speech.
I have to go home soon.
Expressing that something is advisable or expected, but not strictly required.
Means 'had better' or 'should'. Softer than 'have to'. Used for giving advice.
You should go to the hospital.
Expresses moral obligation or duty, 'should' or 'ought to'. Stronger than ほうがいい, but not as forceful as なければならない. Often used in formal contexts.
You should keep your promises.
Both mean 'must' or 'have to', but ならない is more objective (rule, law), while いけない is more subjective (personal feeling, it's bad if not done). In practice, they are often interchangeable.
We must obey the law.
I have to go home now.
English 'have to' can sometimes be used for strong advice, but in Japanese, using なければならない for advice can sound too forceful. Use ほうがいい or べきだ instead.
Do I have to do it now?