La madre de Pedro dice que él ha cambiado mucho desde que trabaja, pero a mí no me lo parece.Pedro's mother says he's changed a lot since he started to work, but I don't think so.
Mi trabajo de voluntariado me ha influido mucho: ha cambiado mi perspectiva de la vida.My voluntary work has had a great influence on me; it's changed my perspective on life.
Bien puede decirse que, con su valentía y rectitud, ha cambiado el destino de nuestro país.It can well be said that you've changed the fate of our country with your courage and rectitude.