～ざるを得ない
have no choice but to
～ざるを得ない attaches to the negative stem of a verb and means “have no choice but to” or “cannot help but”. ざる is a classical negative (“not doing”), and 得ない means “cannot get”. Literally, it means “I cannot get away with not doing it”.
It belongs to formal and written Japanese. Unlike the conversational ～しかない, ～ざるを得ない strongly emphasizes reluctance: circumstances force the action even though the speaker would rather not do it.
1. Being forced to accept or do something
Use ～ざるを得ない when the situation leaves no realistic alternative.
事実を認めざるを得ない。
“I have no choice but to admit the facts.”
- 事実（じじつ）= the facts, the truth
- を = object marker
- 認めざるを得ない（みとめざるをえない）= have no choice but to admit
2. する verbs: せざるを得ない
The irregular verb する becomes せざるを得ない (not しざるを得ない). This form is very common with する compounds like 中止する or 変更する.
台風のため、旅行は中止せざるを得なかった。
“Because of the typhoon, we had no choice but to cancel the trip.”
- 台風（たいふう）= typhoon
- のため = because of
- 旅行（りょこう）= trip
- は = topic marker
- 中止せざるを得なかった（ちゅうしせざるをえなかった）= had no choice but to cancel
How to form it
Verb ない-stem + ざるを得ない (する → せざるを得ない, 来る → 来ざるを得ない（こざるをえない）)
- 認める（みとめる）= to admit → 認めざるを得ない（みとめざるをえない）= have no choice but to admit
- 行く（いく）= to go → 行かざるを得ない（いかざるをえない）= have no choice but to go
- する = to do → せざるを得ない（せざるをえない）= have no choice but to do
Key idea
～ざるを得ない describes an action squeezed out of you by circumstances: you do it not because you want to, but because not doing it is impossible.
Other N2 grammar
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