run out of steam
失去動力或能量，力不從心
口語·描述疲憊無力
英文釋義
to lose energy, motivation, or momentum; to tire or exhaust
例句
After three hours of studying, I ran out of steam.
典故來源
源自蒸汽機燃料耗盡停止運轉，比喻人失去能量或動力。