"caprice" in Chinese (Simplified)
任性反复无常
Definition
突然而不可预测的情绪或行为变化，或出于一时冲动、没有理由地想做某事。
Usage Notes (Chinese (Simplified))
常用于正式或文学语境，很少在口语中出现。常与“命运的变幻无常”等表达搭配；和“心血来潮”类似，但较为优雅。
Examples
His moods changed with every caprice of the weather.
他的情绪随天气的每一个**反复无常**而变化。
Sometimes life seems to move by the pure caprice of fate.
有时候生活仿佛完全由命运的**变幻无常**推动。
Her decision to travel was a simple caprice.
她决定去旅行，只是一时的**任性**。
The artist changed his style on a caprice.
那位艺术家因一时的**任性**改变了风格。
Buying the expensive watch was a caprice he later regretted.
买昂贵的手表是他的一个**任性**，后来他后悔了。
She decorated her room on a caprice, picking colors without any plan.
她全凭一时的**任性**装饰了房间，颜色随意挑选。