Nescio tam multis quid scribas, Fauste, puellis.
Hoc scio, quod scribit nulla puella tibi.
"I don't know, Faustus, what you write to so many girls.
This I do know for a fact, that no girl writes to you."quod [indicativo cum modo]
= "[for a fact] that"
I'm writing in Latin hoping for correction, and not because I'm confident in how I express myself. Latinè scribo ut ab omnibus corrigar, non quod confidenter me exprimam.