you will tell him/her
J'ai rien à promettre, tu lui diras ce que tu voudras.
I have nothing to promise; tell him whatever you want.
— Tout sur ma mère (1999)
You will tell him yourself.
You’ll tell him where it hurts.
What will you tell him?
Will you tell him?
Qu'il commence par t'épouser, tu lui diras après.
Let him marry you first; then you can tell him.
— Moscou ne croit pas aux larmes (1980)
Will you tell him why?