Questions & Answers about Moja sestra želi fotografiju sa porodicom.
Because it is in the accusative case, not the dictionary form.
- fotografija = nominative singular, the basic form
- fotografiju = accusative singular
In this sentence, želi means wants, and the thing being wanted is the direct object, so Serbian uses the accusative:
- Moja sestra želi fotografiju. = My sister wants a photograph.
This is very common with feminine nouns ending in -a:
- nominative: knjiga
- accusative: knjigu
So:
- fotografija → fotografiju
Because the preposition sa / s(a) usually requires the instrumental case when it means with.
- porodica = nominative
- porodicom = instrumental
So:
- sa porodicom = with the family
This is a very important pattern in Serbian:
- sa prijateljem = with a friend
- sa sestrom = with my sister
- sa porodicom = with the family