that you tell him or her
J'en reviens pas que tu lui dises de ne pas perdre le sens de l'humour.
I can't believe you're telling them not to lose their sense of humor.
— Toni Erdmann (2016)
Je veux que tu lui dises que tu vas m'emmener à l'hôpital.
I want you to tell him/her that you're going to take me to the hospital.
— Marty Supreme (2025)
You have to tell him.
Il est temps que tu lui dises la vérité.
It's time you told him the truth.