Eso tengo que verlo
This is like the English way of saying: This I gotta see!
I can understand "that" instead of "this" but I don't know why the extra "lo" is needed when you already have eso. Gracias
1 Answer
When the D.O. appears before the verb, the corresponding pronoun also appears with it:
Eso... [D.O.] tengo que ver[lo: D.O.]