This is the 5903rd most frequent Polish word.
zielenią
"Zielenią" means "they/it turn(s) green" or "with greenery," depending on the context.
In this sentence, "zielenią" refers to the lush green vegetation and is used as a noun.
Park jest piękny, szczególnie wiosną, pełen świeżej zieleni.
The park is beautiful, especially in spring, full of fresh greenery.
Here, "zielenią" is used as an instrumental case noun to represent the green color or hues in the context of art.
Malując obraz, artysta ożywił krajobraz żywą zielenią.
While painting the picture, the artist enlivened the landscape with vibrant green hues.
"Zielenią" again is a noun in the instrumental case, describing the green aspects of gardens.