Translation guide
The concept of obligation in Japanese is expressed through various grammatical patterns and vocabulary that convey duty, necessity, or social expectation. The most common ways include 〜なければならない (must/have to), 〜べき (should/ought to), and nouns like 義務 (duty/obligation). The choice depends on whether the obligation is personal, social, moral, or legal, and the level of formality.
Expressing that someone must do something due to rules, circumstances, or personal necessity.
The standard way to say 'must' or 'have to'. It implies a strong obligation, often from external rules or common sense. Can be shortened to 〜なきゃならない in casual speech.
明日までにレポートを提出しなければならない。
I have to submit the report by tomorrow.
I must take my medicine every day.
A slightly more colloquial alternative to 〜なければならない. Often used in spoken Japanese. Shortened to 〜ないと in casual conversation.
もう行かないといけない。
I have to go now.
宿題をやらないといけない。
I have to do my homework.
Similar to 〜なければならない but slightly more formal or emphatic. Often used in written language or formal speech.
規則を守らなくてはならない。
We must follow the rules.
Another variation, interchangeable with 〜なければならない. Slightly less common but still widely understood.
急がなければいけない。
We have to hurry.
Expressing that something is the right thing to do based on morality, social norms, or advice.
Used to say 'should' or 'ought to' based on moral duty, common sense, or strong recommendation. The negative form is 〜べきではない (should not).
約束は守るべきだ。
You should keep your promises.
もっと勉強するべきだ。
You should study more.
While primarily meaning 'supposed to' or 'expected to', it can imply an obligation based on a plan or arrangement. Use with caution as it often just means 'it should be the case that'.
Not a direct equivalent of 'obligation'; only use when the obligation is based on a logical expectation or schedule.
彼はもう着くはずだ。
He should arrive soon. (expectation)
Used to express a general social or moral obligation, often in a reflective or advisory tone. Translates to 'one should' or 'it is a rule that'.
年上には敬語を使うものだ。
One should use polite language with elders.
Referring to a duty or obligation as a concept, often in legal, business, or formal contexts.
The most direct translation for 'obligation' as a noun. Used for legal, moral, or social duties.
納税は国民の義務だ。
Paying taxes is a citizen's obligation.
彼にはその義務がある。
He has that obligation.
A more formal term for duty or responsibility, often used in official or business contexts.
Primarily means 'responsibility', but can overlap with 'obligation' in contexts where one is bound to do something.
Expressing that circumstances force someone to do something, often with a nuance of reluctance.
A formal pattern meaning 'cannot help but do' or 'have no choice but to'. Used when external factors compel an action.
悪天候のため、試合は中止せざるを得なかった。
Due to bad weather, we had no choice but to cancel the game.
A more casual way to say 'there is no choice but to'. Often used in spoken Japanese.
やるしかない。
I have no choice but to do it.
Expressing that one must not do something, i.e., a negative obligation.
The standard way to say 'must not' or 'may not'. Used for prohibitions based on rules or strong advice.
ここでタバコを吸ってはいけない。
You must not smoke here.
Used to say 'should not' based on moral or social norms.
嘘をつくべきではない。
You should not lie.
〜なければならない expresses a strong, often unavoidable obligation (must/have to), while 〜べきだ expresses a moral or advisable obligation (should/ought to). Use 〜なければならない for rules and necessities, and 〜べきだ for advice and ethical duties.
法律を守らなければならない。
We must obey the law. (strong obligation)
法律を守るべきだ。
We should obey the law. (moral advice)
English speakers often try to use 義務 (gimu) in every context where 'obligation' appears, but Japanese often prefers verb patterns like 〜なければならない or 〜べきだ to express the idea naturally. Reserve 義務 for formal, legal, or abstract discussions of duty.
To fulfill that obligation.
責任を持って行動する。
To act with responsibility (obligation).