Grammar Info

N1 Lesson 10: 8/22


Will definitely, Will certainly, Bound to, Not fail to

also used to express that subject (usually non-animate like a book) has an emotional effect on people


Verb [ない-stem] + ずには + おかない
Verb [ない] + では + おかない

Verb [Negative] + では + おかない


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About ずにはおかない

ずにはおかない is a combination of the classical auxiliary verb ず, the case-marking particle に, the adverbial particle は, and the standard negated form of the う-Verb ()く, ()かない, ‘to set aside’, or ‘to leave as is’. It is interpreted as ‘(A) will definitely happen’, or ‘I will not fail to (A)’.
This is a formal expression that literally means ‘I cannot leave it as it is with (A) undone’, and therefore indicates strong will to complete the action that is reflected in the standard translations.
As this structure begins with ず, it will only be used with verbs.
  • あんなひどいことをした(ひと)だから、警察(けいさつ)(つか)まえずにはおかないだろう。
    I am sure the police will not fail to arrest that person, since they did something so horrible.
  • メディアにも(とり)()げられたから、警察(けいさつ)調査(ちょうさ)をせずにはおかない
    Since it was covered by the media, the police will certainly investigate.
Alternatively, ないでは may replace ず. This will be seen as ないではおかない. However, the meaning will not change at all.
  • こんなことをされたのだから、お(きゃく)さんも(うった)ないではおかないだろう。
    Since they did such a thing to the customers, they would certainly sue them.
  • この(いぬ)は30キロになるから、(しつけ)(ちから)()ないではおかない
    Since this dog will become 30kg, I will not fail to train him.
Due to this grammar expression showing strong will to not give up until (A) is done, it will often be used with causative verbs in (A). This indicates that the speaker is determined not to quit until they can make another person do something.
  • あの(ひと)のスピーチは()(ひと)感動(かんどう)させずにはおかない
    That person’s speech will not fail to move the audience.



  • 小説(しょうせつ)勇者(ゆうしゃ):「どんな手段(しゅだん)(もち)いても、かならず魔王(まおう)(たお)ずにはおかない。」

    Novel: 'No matter what it takes, I will not fail to defeat the Demon Lord!'

    • (わたし)はきっと(かれ)(おな)()仕返(しかえ)しをしないではおかない。」

      'I won't fail to pay him back in his own coin.'

      • 警察(けいさつ)はすべての悪者(わるもの)(かなら)(ばつ)(あた)ずにはおかない。」

        'The police will not fail to punish all the wicked people.'

        • (かれ)はまた(わたし)との約束(やくそく)をすっぽかした。絶対(ぜったい)(かれ)に『ごめんなさい』と()わせずにはおかない。」

          'He skipped our appointment again. I won't fail to get him to say "I'm sorry".'

          • 小説(しょうせつ):「探偵(たんてい)は『この残虐(ざんぎゃく)行為(こうい)責任者(せきにんしゃ)訴追(そつい)ずにはおかない』と()(けっ)する。」

            Novel: 'The detective resolved himself, "I won't fail to bring the person responsible for this atrocity to justice".'

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            ずにはおかない – Grammar Discussion

            Most Recent Replies (3 in total)

            • wrt7MameLZE33wlmpCAV


              The verb here is 置く right? I’m trying to internalize what this means literally, although I suspect this is going to trip me up the same way ずにはいられない・てはいられない・わけにはいかない continue to.

            • Fuga


              Hey @wrt7MameLZE33wlmpCAV !

              The おく used here is actually 措く, which mean to ‘stop something in the middle of’. 置くis used for physical things, while 措く is used for something more conceptual.

              箸を置く。is ‘to place your chopsticks down’, but 箸を措く。means ‘to stop eating’.

              So the literal meaning of 〜ずにはおかない, would be ‘would certainly not stop without [verb]’. So, for example, 絶対に「ごめんなさい」とわせずにはおかない’s literal translation would be ‘I will certainly not stop without making him say that he is sorry’ with the nuance of ’ I won’t fail to get him to say ‘I’m sorry’ because the speaker has a strong will to make the person say that he is sorry, and there is nothing that will stop the speaker from doing so.

              I hope that answers your question!

            • wrt7MameLZE33wlmpCAV



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