"I have a sandwich and fruit."
Translation:Mam kanapkę i owoce.
With "mieć" (to have) you use Accusative. "Kanapka" is a feminine noun so in Accusative it becomes "kanapkę". "Owoce" is plural form of "owoc" (masculine noun). Here Accusative form is the same as Nominative form. Look at the tables of declension: https://en.wiktionary.org/wiki/kanapka https://en.wiktionary.org/wiki/owoc
What exactly are Accusative and Nominative? People seem to just use those words as explanations and I'm struggling to figure out what they mean exactly.
I see her.
She sees me.
Polish has much more complicated case system than English. We have 7 cases.
Nominative is a "dictionary" form of word (in singular) is a case used for subject of the sentence, when the noun/pronoun is the one "active", doing a thing, when you would use "I" in a sentence. also if a sentence has "to jest" phrase in it.
Accusative is for direct object. I see her, I eat fruit. I have a sandwich
Most verbs in Polish (in positive statements) need object in accusative case. Also there are some prepositions that need nouns in accusative.
kanapkę is the accusative case of kanapka, which you need here, because it is the direct object.
Just for the sake of clarity, the word 'fruits' mostly exist in botanical studies and even there usually means multiple kinds of fruit – 'normal' English has irregular plural 'fruit' for the word 'a fruit', so:
- „gruszka i jabłko” = 'fruit' or rarely 'fruits' but „owoce” in Polish
- „dwie gruszki” = 'fruit' = „owoce”
- „jedna gruszka” = 'a fruit' = „owoc”