work on
US /wɜːrk ɑːn/
UK /wɜːrk ɑːn/

1.
2.
trabajar en, persuadir
to try to influence or persuade someone
:
•
I've been working on him to change his mind.
He estado trabajando en él para que cambie de opinión.
•
She's been working on her parents to let her go to the party.
Ha estado trabajando en sus padres para que la dejen ir a la fiesta.