These exercises are bringing in the use of Dative case. Previously, we have largely used accusative for verbs or genetive if negating verbs. One verb used in prior exercises was "dostarczyc", where we would use accusative/genetive as I described.
My question is, if we changed this sentence to "Dlaczego dostarczasz nam stare gazety"... is "nam" still correct or would you use the accusative "nas"?
I'm just trying to get my head around whether "wysyłasz" is requiring Dative here because it is just a rule, or does it require Dative because of the way it is used in this sentence.
If the latter, then "Dlaczego dostarczasz nam stare gazety" would also be correct because you are using the verb in the same manner... And if that's the case, then all the prior exercise where we used verbs were carefully selected so the Dative case was not required??!
With verbs such as "dostarczać", there are two objects. The thing that gets delivered (direct object), and the recipient of the delivery (indirect object). The first one takes Accusative, the latter takes Dative. There were some sentences without the recipient (before introducing Dative), they probably could be better - although of course 'delivering' may just be a job so it won't have any specific recipient.
So "Dlaczego dostarczasz nam stare gazety" grammatically works exactly the same as the sentence here. If you wrote "Dlaczego dostarczasz nas" (Accusative), then it would mean that 'we' are the thing that gets delivered ;)