This is the 139th most frequent Czech word.
rusko
"Rusko" in Czech means "Russia" in English.
Here, 'Rusku' is the dative case form of the noun 'Rusko', referring to the country of Russia, indicating the recipient of the action.
Rusku se podařilo vyvinout nový vesmírný program.
Russia managed to develop a new space program.
In this case, 'Rusko' is in its nominative form, as it is the direct object of the action, representing the country of Russia.
Každý rok naše rodina navštěvuje Rusko.
Every year our family visits Russia.
Here, 'Rusku' appears again in the locative case, showing the context or topic of the movies, referring to Russia.