This is the 28th most frequent Italian word.
suo
"His," "her," "its," or "their" (possessive adjective).
Possessive adjective indicating ownership.
Questo è il suo libro.
This is his/her book.
Possessive adjective specifying a relationship.
Suo padre lavora in città.
His/Her father works in the city.
Possessive pronoun used for emphasis in a formal way.