"He does not depend on his parents."
Translation:Il ne dépend pas de ses parents.
Why can't I write "sur" instead of "de"? Is there a particular rule that is connected to it? Because when you directly translate "on", it's "sur" so that's what made more sense to me...
Prepositions may or may not match from one language to the other.
rely on = dépendre de
responsible for = responsable de
shoot at = tirer sur
"Dependre de" is a verb + preposition combination which means "to depend on". Conjugate correctly for "depend de". Sur on its own isn't used with the indirect object (I think) but can be used with other verbs such as "concentrer sur" that also uses an indirect object. In this case "dependre de" is most appropriate.
"Compter" means to rely on someone/something. Here it is more a matter of to be dependant of someone. I think it's a stronger meaning.
yes it is more precise also: it means that he can pay his bills without his parents' help.
Is there a good way to remember when to use "À" , "De" , "Sur" etc ? I am always bamboozled by these!