From the Warring States era assassin's farewell in 《战国策》: 风萧萧兮易水寒,壮士一去兮不复还 — Jing Ke's vow as he set out to kill the King of Qin. One of the most quoted lines in classical Chinese.
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Highly literary. In modern prose it evokes autumn, desolation, or aging. Rare in speech.