This is the 4609th most frequent Polish word.
miastem
"Miastem" is the instrumental case of "miasto," meaning "city" or "town" in English.
This sentence employs 'miastem' in a figurative context, illustrating the instrumental case to symbolize a state of being or identity.
Byłem kiedyś miastem otoczonym przez rzeki.
I once was a city surrounded by rivers.
In this sentence, 'miastem' is the instrumental case of 'miasto' used with 'jest', expressing the quality of being a city.
Kraków jest pięknym miastem.
Kraków is a beautiful city.
Here, 'miastem' is used descriptively to attribute the characteristic of being a 'city of culture' through a complementary structure.