"I am eating an apple and drinking tea."
Translation:Jem jabłko i piję herbatę.
herbata, pies - the Nominative case. The basic form of the noun, used mostly for the subject of the sentence.
herbatę, psa - the Accusative case, used mostly for the direct object of the sentence.
herbatą, psem - the Instrumental case, used mostly after "z" ("with") and in sentences built like "Lassie jest psem" ("Lassie is a dog").