tú preguntártelo

to ask you about it

→ preguntar
pregunt to ask + ár infinitive ending + te 2nd-person singular indirect object + lo Direct object pronoun (masculine singular or gender-neutral)
verb · second Rare #42,403
to ask you about it The pronouns mean “you” (informal singular) and “it”; the infinitive is used with attached pronouns.
SP: Voy a preguntártelo mañana.
EN: I'm going to ask you about it tomorrow.
Conjugation of preguntar

Y tiene la cara de preguntártelo.

And she has the face to ask you.

— Haz lo que debas (1989)

No me hagas preguntártelo otra vez.

Don't make me ask you again.

Pensé que podría preguntártelo.

I thought I could ask you.

— Dil se.. (1998)

Marco, siempre he querido preguntártelo.

Marco, I've always wanted to ask you.

— Hable con ella (2002)

No me hagas preguntártelo de nuevo.

Don't make me ask you again.