A girl's signature doesn't necessarily mean she has a boyfriend. Early understanding of lanyin is an idiom. On the surface, it means early understanding of the impermanence of marriage, and by extension, it means early understanding of the impermanence of the world. This signature may express the girl's feelings and thoughts about life and love, rather than directly indicating whether she has a boyfriend. Therefore, it is impossible to judge whether a girl has a boyfriend by a signature, and further observation and understanding are needed.