whistle in the dark
徒劳无益地试图保持镇静或充满信心
口语·表达强装镇定或乐观
英文释义
to remain optimistic or hopeful in a difficult or uncertain situation
例句
He knew the exam was tough, but he kept whistling in the dark to calm his nerves.
典故来源
源自人们在黑暗或危险环境中吹口哨以壮胆的行为，比喻试图掩饰恐惧或保持乐观。