This is the 1610th most frequent Polish word.
lato
"Summer."
Here, 'lato' is used as a noun referring to the season of summer.
Lato jest moją ulubioną porą roku.
Summer is my favorite season.
In this context, 'lato' is modified to 'lecie' to fit the prepositional phrase, referring to the specific summertime.
W zeszłym lecie pojechaliśmy na Mazury.
Last summer, we went to Masuria.
The plural form 'lat' is used here to signify 'years', showcasing its broader application in Polish grammar.