I generally go to the gym or go for a run, especially if I've had a bad day.

我通常会去健身房或者去跑步，尤其是当我度过了糟糕的一天的时候。

youdao

Does it lift your spirits on a bad day, or does it annoy you because there's nothing happy about this particular holiday this year?

它会让你在糟糕的日子里振作起来，还是会让你因为今年这个特别的节日没有什么快乐的事情而烦恼？

youdao

OK, so you had a bad day. Don't take it out on me.

好，这么说你今天遇上了很多倒霉事。可也别拿我当出气筒。

《牛津词典》

Recently,my brother had a bad day at the office.

VOA: special.2009.07.19

She's just having a bad day.

她只是今天过得不太顺利。

You look 课堂 - SpeakingMax英语口语达人

All right, you can't sue Yale later if you had a bad hair day.

发现你糟糕的发型可别起诉耶鲁大学

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Much depends on whether Dad is having a good day or a bad day.

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On a bad day, the queue at passport control stretches almost to the runway.

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

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