if you promise
Si prometes algo, mantén tu palabra.
If you promise something, keep your word.
Si prometes cenar conmigo hoy, te contaré todo.
If you promise to have dinner with me today, I'll tell you everything.
— Taxi (1998)
Te lo digo si prometes que no la lastimarás.
I'll tell you if you promise not to hurt her.
— Tropa de Élite (2007)
Te lo digo si prometes venir a verme al teatro.
I'll tell you if you promise to come see me at the theater.
— Dolor y gloria (2019)
Pero sólo si prometes no molestar a ninguno de los profesores.
But only if you promise not to bother any of the teachers.
— मुन्ना भाई एम बी बी एस (2003)