This is the 1398th most frequent Polish word.
sukcesu
"Success."
Here 'sukcesu' is the genitive form of 'sukces', used to indicate possession or relation.
Cała drużyna cieszyła się ze swojego sukcesu.
The whole team was celebrating their success.
In this sentence, 'sukcesu' functions as a direct object in a sentence with a negative verb, which requires the genitive case in Polish.
Bez ciężkiej pracy osiągnięcie sukcesu jest niemożliwe.
Without hard work, achieving success is impossible.
Here, 'sukcesu' is used in the genitive case to describe an abstract relationship, providing information about the scope or nature of the beginning.