belong就是属于，比较常见的用法就是belong to
比如：The book belongs to her.
但是我们看电影听歌曲经常听到belong with ,两者有啥区别，区别就是
"Belong to" 表达所有权（ ownership）比如 That cellphone belongs to me.
"Belong with" 表示某些事物人应该在一起，比如Taylor Swift 的歌 you belong with me
那么为啥不用you belong to me？这里是一个很好的解释
'You belong with me' suggests that destiny has thrown the two of you together, that you are a perfect match. It's very romantic.
'You belong to me' probably used to be said by husbands to wives but hopefully no longer is, since it suggests domination and ownership, rather like a master and slave. Let's just say it's not very romantic.