ずにはおかない / ないではおかない means will definitely do; cannot not ~. It is a JLPT N1 Japanese grammar pattern used to express that a person, thing, or situation inevitably causes a certain effect—the subject’s quality or action makes the outcome unavoidable.
This grammar point often appears in editorials, reviews, passionate commentary, and JLPT N1 reading passages. If you want to state that something is bound to make someone feel or act in a particular way, ずにはおかない / ないではおかない adds weight and natural dramatic force to your Japanese.
What does ずにはおかない / ないではおかない mean?
Use ずにはおかない / ないではおかない when you want to express that a person, thing, or situation inevitably causes a certain effect—the subject’s quality or action makes the outcome unavoidable.
Natural translations include:
- will definitely do; cannot not ~
- is bound to make (someone) do / feel …
- never fails to cause …
Try to notice what is causing the effect and who or what experiences it, then choose the English phrase that captures the inevitability.
How to form ずにはおかない / ないではおかない
Two parallel patterns exist. They attach to verbs and are equivalent in meaning; the choice is a matter of style.
Pattern 1: ずにはおかない (classical negative stem)
- For する → せずにはおかない
- For くる → こずにはおかない
Pattern 2: ないではおかない (modern negative form)
- For する → しないではおかない
- For くる → こないではおかない
The pattern takes a transitive or causative verb that describes an effect on something else. You cannot use it for purely self‑focused actions. In JLPT questions, distractors often try to attach ずにはおかない to an intransitive verb where only an external effect makes sense.
When is ずにはおかない / ないではおかない used?
Use ずにはおかない / ないではおかない in situations like:
- reviewing books, films, or performances to say “it will absolutely move you”
- criticising behaviour that inevitably provokes a reaction
- making strong assertions about historical or social forces
- expressing personal predictions with emotional certainty
Tone and register:
- formal to semi‑formal; common in written commentary, speeches, and news analysis
- conveys intensity, not casual chat
- often followed by ～だろう to soften a prediction, or used directly for a bold claim
ずにはおかない / ないではおかない example sentences
After reading each sentence, ask what job ずにはおかない / ないではおかない is doing: stating that the subject’s nature or action guarantees a particular effect.
Nuance of ずにはおかない / ないではおかない
The key nuance is irresistible cause‑and‑effect. The speaker is not just saying “probably” — they are asserting that the effect is unavoidable, given the subject’s intensity or qualities.
This differs from patterns that describe internal urges (like ずにはいられない). Here the focus is external: somebody or something forces a reaction in a third party. That is why you rarely use ずにはおかない about your own sleep or meals — you use it about a movie that moves viewers, a speech that angers the public, or a performance that astonishes everyone.
ずにはおかない / ないではおかない vs ずにはいられない
Both patterns share the ずには… element, but they differ in direction and scope.
If both translations seem possible, check the subjects: is the grammar point describing a force that makes somebody else react? Or a personal, uncontrollable impulse? The answer tells you the correct pattern.
Common mistakes with ずにはおかない / ないではおかない
A helpful practice method is to write one sentence with ずにはおかない, then rewrite it with ずにはいられない.
Is ずにはおかない / ないではおかない on the JLPT?
ずにはおかない / ないではおかない is commonly taught as JLPT N1 grammar.
That means learners should be able to:
Pay attention to who or what is the agent and who receives the effect.
Practice questions for ずにはおかない / ないではおかない
Once the structure feels natural, add more context so the causal chain becomes clear.
Learning path for ずにはおかない / ないではおかない
To learn ずにはおかない / ないではおかない efficiently, start with its formation, then compare it with similar patterns, and finally practice in context.
Related grammar to review next
- ずに済む — because it also uses ずに, but with the opposite nuance (getting by without doing something)
- ずには済まない／ないでは済まない — because it shares the “cannot be left undone” structure, but focuses on obligation rather than inevitable external effect
- ずとも — because it contrasts with the older ず negative, showing a more formal alternative
- ぞ／ぜ — because both sentence‑ending particles add emphasis, and the assertive tone overlaps with the confidence of ずにはおかない
Learn ずにはおかない / ないではおかない with Hane
If you want to review ずにはおかない / ないではおかない together with the related patterns above, Hane helps you practice Japanese in short, focused sessions.
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FAQ about ずにはおかない / ないではおかない
What does ずにはおかない / ないではおかない (zu niwa okanai / nai dewa okanai) mean in Japanese?
ずにはおかない / ないではおかない (zu niwa okanai / nai dewa okanai) means “will definitely do; cannot not”. It is JLPT N1 grammar. Use ずにはおかない / ないではおかない when you want to express that a person, thing, or situation inevitably causes a certain effect—the subject’s quality or action makes the outcome unavoidable.
How do you form ずにはおかない / ないではおかない (zu niwa okanai / nai dewa okanai)?
Two parallel patterns exist. They attach to verbs and are equivalent in meaning; the choice is a matter of style.
What is the difference between ずにはおかない / ないではおかない and ずにはいられない?
ずにはおかない / ないではおかない: external inevitability. ずにはいられない: internal compulsion.
What is an example sentence with ずにはおかない / ないではおかない (zu niwa okanai / nai dewa okanai)?
観客を感動させずにはおかない。 — This film will definitely move the audience.