- fare vedere = to show
- glielo = gli (a lui = to him) + lo (it) = it to him
so it can be translated as well as: "I'll show it to him" or "I am showing it to him" (they are marked as correct)
Glielo is a double object pronoun. The indirect object pronouns combined with the direct object pronouns form the double object pronouns.
more about them you can see here: http://www.cyberitalian.com/en/html/gra_prpr.html
to show = far(e) vedere, mostrare
If I'm not mistaken it's usually written as far vedere. example :
- Mi può far vedere sulla pianta?
- Mi può mostrare sulla mappa?
both sentences are translated as "Can you (formal you) show me on the map?"
EDIT: Thanks Viaggiatore, for pointing it out.
So, Viaggiatore... I'm sure you're right, and forgive my thickness, but how can it be also "I'll show her", if "to her" is usually "le", isn't it?
And while I'm at it, I very unimaginatively typed "gli mostrerò" - any good at all? (why is the present tense used here?) Thank you, and I'm also breathless with anticipation, to say the least... :)
When you have two object pronouns together before the verb, the game changes. Look here: http://italian.about.com/library/fare/blfare168a.htm One of the weirder features.
Sometimes one language uses the future where the other uses the present. "Gli mostrero'" looks fine to me.