This is the 904th most frequent Czech word.
marek
The Czech word "marek" is a given name, equivalent to "Mark" in English.
Here, 'Marek' is a given name used as a subject in a personal context.
Marek je můj nejlepší přítel.
Marek is my best friend.
In this case, 'Marek' is a given name acting as the subject who performs an action.
Marek koupil nový vůz.
Marek bought a new car.
Here, 'Marek' is used as a name in the accusative case as the object of the verb 'know'.