Also "Jem arbuza" (I eat a watermelon) and many other tasty things of Masculine grammatical gender. It may sound strange to speakers of some other Slavic languages, because only animate nouns of masculine grammatical gender change their form in Accusative there, while inanimate nouns have the same declension as Nominative.
Thanks for the link, it's very useful, there are answers for some hard moments that may happen while studying Polish. Yesterday I was googling jem+kind of food, but unfortunately most of them were Feminine (cebula, cytryna erc) and then I stumbled upon "jem arbuza" and one page where the teachers of Polish discuss this topic. https://e-polish.eu/forum-metodyczne-dla-nauczycieli-jezyka-polskiego-jako-obcego/jem_arbuz and some other pages, including one that was mentioned above here (ekorekta24.pl...).
Is there a specific way of turning a singular word into a plural? Or is it different for every word?
By this, i mean, how English changes tomato into tomatoes by adding "es" (this isn't the best example because it adds an e as well as an s, but you hopefully get my meaning)