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》

Keith has had a bad day at work, and he is feeling old.

基思今天工作不顺利，而且他觉得自己老了。

youdao

A good friend will cheer you up when you are having a bad day.

好朋友会在你心情不好时让你振作起来。

youdao

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

耶鲁公开课 - 博弈论课程节选

In fact, toward the end of a bad day, it can start to feel downright personal!

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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.

ECONOMIST: To understand contemporary Russia, consider its airports