I am having such difficulties with the cases. Here, "animals" is the direct object. However, it appears in its' nominative form. I was expecting it to be in another case/form. While I do not know which case I would have expected/guessed, I am still so surprised that it is nominative. yeesh!!!
It is in accusative. It is just that animal=zwierzę is neuter , and neuter words have accusative=nominative in both singular and plural.
Kochamy dziewczynkę (nom dziewczunka=girl) Kochamy dziewczynki (nom dziewczynki=girls)
kochamy dziecko (nom dziecko=child) kochamy dzieci (nom dzieci=children)
kochamy chłopca (nom chłopiec = boy) kochamy chłopców (nom chłopcy=boys)
masculine not personal animated
kochamy psa (nom pies=dog) kochamy psy(nom psy=dogs)
masculine not animated
kochamy stół (nom. stół=table) kochamy stoły (nom stoły=tables)
unfortunately not. there are some rare exceptions that never change, but as a rule all nouns change, but they never have all 14 different forms. accusative is a very specific case where only feminine singular has it's own form, while other have either accusative=genitive or accusative=nominative.