JLPT N1Written, formalForceful

ないではおかない・ずにはおかないwon't leave it undone; can't fail to

Someone will not leave a thing undone: "I won't rest until I have". Or a thing is so powerful that a reaction can't fail to follow: "it is bound to". Written and forceful, for reading.

私わたしは真しん相そうを必かならず突つき止とめずにはおかない。

I will not rest until I have gotten to the truth.

その静しずかなラストシーンは、観かん客きゃくを深ふかく感かん動どうさせずにはおかない。

That quiet final scene can't fail to move an audience deeply.

How to form it

Verb ない-form: ない → ずにはおかない／ないではおかない　　する → せずにはおかない

突つき止とめない → 突つき止とめずにはおかない, 突つき止とめないではおかない. The same meaning; ずには is the more common.

A person: Someone with a truth to get at or a score to settle. It can sound like a threat.
A thing: A film, a book, a speech, a ruling. The verb is what it does to people, usually a causative: 感かん動どうさせる, 考かんがえさせる.
Where you'll meet it: Reviews, criticism, editorials, novels. For the vow, people say 絶ぜっ対たいに…する.

ずにはすまない and ずにはおかない

これだけの被ひ害がいが出でた以い上じょう、会かい社しゃは事じ故この原げん因いんを明あきらかにせずにはすまない。

With this much damage done, the company can't get out of bringing the cause of the accident to light.

"Can't get out of it": duty pushes the company. It would rather not.

何なん年ねんかかっても、私わたしは事じ故この原げん因いんを明あきらかにせずにはおかない。

However many years it takes, I will not rest until I have brought the cause of the accident to light.

"Won't leave it undone": I do the pushing. Nobody is making me.

In use

この記き録ろく映えい画がは、見みる者ものに戦せん争そうの記き憶おくについて考かんがえさせずにはおかない。

This documentary can't fail to make its viewers think about the memory of war.

この判はん決けつは、企き業ぎょうに安あん全ぜん基き準じゅんの見み直なおしを迫せまらずにはおかない。

This ruling is bound to press companies into reviewing their safety standards.

Not a causative, but still something done to someone.

政せい府ふの説せつ明めいに矛む盾じゅんがある以い上じょう、記き者しゃ団だんは真しん相そうを追つい及きゅうしないではおかない。

Given the contradictions in the government's account, the press corps will not let the truth go unpursued.

Not ずにはいられない

ずにはいられない, "can't help", starts from the person who feels. Here the subject is what moves them.

その話はなしを聞きくと、笑わらわずにはいられない。

Whenever I hear that story, I can't help laughing.

I am the subject.

その話はなしは、聞きく人ひとを笑わらわせずにはおかない。

That story can't fail to make people laugh.

The story is the subject, and makes them laugh: a causative.

Close neighbours

ないではすまない・ずにはすまないN1

"Can't get out of doing": the subject is pushed. Duty or the situation leaves no way out.

製せい品ひんの欠けっ陥かんで事じ故こが起おきたのだから、メーカーは被ひ害がい者しゃに補ほ償しょうせずには済すまない。

The accident was caused by a defect in the product, so the maker can't get out of compensating the victims.

考えさせられるN4

What people say: the same thing from the side of the person moved.

この映えい画がにはいろいろ考かんがえさせられました。

This film gave me a lot to think about.

Check yourself

1Which one fits?

この小しょう説せつは、読よむ人ひとの心こころを（　　）。

Choose an answer to see why.

2Which one fits?

彼かれのスピーチを聞きいて、私わたしは（　　）。

Choose an answer to see why.

More sentences

彼かの女じょの演えん説ぜつは、聴ちょう衆しゅうに自じ分ぶんたちの責せき任にんを意い識しきさせないではおかない。

Her speech can't fail to make the audience conscious of their own responsibility.

彼かれの告こく発はつは、関かん係けい者しゃに従じゅう来らいの慣かん行こうを問とい直なおさせずにはおかないだろう。

His accusation will surely force those involved to question the way things have always been done.