她年轻时有过一些短暂的恋情，但从未认真过。

She had a few dalliances in her youth, but never anything serious.

dalliances 是名词 dalliance 的复数形式。dalliance 来自动词 dally（闲荡、嬉戏），加上名词后缀 -ance 构成，原指"嬉戏、消遣"，引申为"短暂的恋爱关系"或"不认真的感情纠葛"。