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to be disheartened; to lose heart; to be dispirited; to be crushed (emotionally)
to be sprained
to be snapped; to be broken
大怪我で一度は心が挫けた。
After a serious injury, I almost lost heart once.
何度も挫けても、彼は諦めなかった。
Even after being disheartened many times, he didn't give up.
どんな時も挫けるな。
Don't lose heart no matter what.