You never know what will happen in football and it just takes one bad day to mess things up.

在足球世界中，你永远都不知道会发生些什么。一着走错就有可能全盘尽失。

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One employee having one bad day in a bad way can cause dozens or hundreds of customers to have a bad day.

一个用很糟糕的方式对待自己糟糕的一天的员工能够造成数十或者成百上千的顾客的一天都过得很糟糕。

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But that defeat was the one that mattered and, despite only one bad day, Mourinho has never felt further away from success as he does right now.

但周一的失利是相当严重的事件，尽管只有一次，可穆里尼奥从没感到自己远离成功，正如他现在所做的。

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We had one bad day and to finish four points off the leader is very positive.

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They included distress tolerance techniques like plunging her head into ice water, devising ways to distract herself when bad thoughts arose and learning not to leap to the conclusion that one bad day implies a life of misery.

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It will take more than one bad index day for these gains to be erased.

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