This is the 900th most frequent Czech word.
brno
"Brno" is a Czech proper noun referring to the second-largest city in the Czech Republic.
Here 'Brno' is used as a proper noun, specifically the name of a city in the Czech Republic.
Brno je druhé největší město v České republice.
Brno is the second-largest city in the Czech Republic.
In this sentence, 'Brně' is the locative case of 'Brno', indicating location.
V Brně je mnoho historických památek.
In Brno, there are many historical landmarks.
'Brna' here is the genitive case of 'Brno', used to indicate possession or relation.