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cannot avoid doing; cannot help but (do); is compelled to do; (feel) obliged to (do); has to do
事情を説明せざるを得なかった。
I had no choice but to explain the situation.
彼の意見に賛成せざるを得ない。
I cannot help but agree with his opinion.
計画を変更せざるを得ないだろう。
We will probably have to change the plan.