The possessive determiners, also called possessive adjectives, serve to express ownership or possession (hence the name). Possessive adjectives, like all adjectives in Spanish, must agree with the noun they modify. Thus, if the noun is feminine, the possessive adjective must be feminine, too.
Pues siguen las reglas generales de acentuación, además de: Si el acento cae sobre una de las vocales cerradas, se tilda, pero no se considera triptongo
