情感变化用英语短语怎么说

情感变化可以用英语短语 "mood swing" 来表示。例如：

She has been experiencing mood swings since she started taking that new medication.
He's been going through a lot of mood swings lately. I'm not sure what's going on.

这个短语通常用来描述一个人的情绪会在短时间内剧烈变化，可能是因为生理或心理原因。