She can be a real pain when she's in a bad mood.

她脾气不好时，真是令人头痛。

《牛津词典》

The word came to be associated both with a loud sound and with danger! When someone speaks of a "jovial mood" or a "herculean effort," he or she is using words with origins in mythology.

这个词开始与响亮的声音和危险联系在一起！当有人说到“愉快的心情”或“艰苦的努力”时，他或她使用的词汇源于神话。

youdao

People are ungrateful when in a bad mood.

心情不好的时候，人们就不会表达感激之情。

youdao

It's kind of like , where you had side A,side B and you just flipped it over when you wanted to change your mood so to speak.

VOA: standard.2010.06.18

To establish a diagnosis, a person must have demonstrated, at some point, delusions or hallucinations for at least two weeks even when mood disorder symptoms are under control.

CNN: Schizoaffective disorder

Graniss reminds us that our emotions can get the best of us not only when we are in a bad mood but also when we are in a good mood.

FORBES: Top 10 Emotional Intelligence Moments of 2012

However, like today, 1979-1980 was a perfect buying opportunity, when the mood was darkest.

FORBES: Investor Illusions