all bets are off
一切皆无法预测，没有确定性或保证
口语·表示情况突变无法预测
英文释义
to imply that previously established rules or expectations no longer apply
例句
With the sudden change in weather, all bets are off for the outdoor concert tonight.
典故来源
源于赛马或赌博，当出现意外情况时，所有赌注取消或规则失效。