这是她的戒指 用英语怎么说？

This is her ring.

This/It is her ring.(最通俗)
The ring belongs to her.(强调这戒指属于她)

This is her ring.
或
This ring is hers.
这两句是同义句。

这是她的戒指:This is her ring.一般这样说
专业的说： The ring belongs to her.强调这戒指是属于她的

This is her ring

This is her ring