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(not) by any means; (not) for anything; wouldn't do for anything; had enough; flatly refusing
もう残業は真っ平だ！
I've had enough of overtime!
彼は「真っ平ごめんだ」と、その提案を断った。
He refused the proposal, saying, "No way, I've had enough."
祭りの混雑を思い出し、「もう真っ平だ」と彼はつぶやいた。
Remembering the festival's crowd, he muttered, "I've had enough."