My?
Mi/mis
Your (sing/inf)?
Tu/tus
His/her/your (formal)?
Su/sus
Our?
Nuestro/nuestra
Nuestros/nuestras
Your (plural, informal)?
Vuestro/vuestra
Vuestros/vuestras
Their, your (sing, formal)
Su/sus
My book?
Mi cuaderno
Your mother? (formal)
Su madre?
Our aunts?
Nuestras tías
Your houses (plural)
Vuestras casas