This is the 16263rd most frequent Polish word.
usilnych
"Usilnych" means "persistent" or "strong efforts" in English.
The word 'usilnych' describes the efforts as persistent and sustained in nature, enhancing the descriptive quality of the noun it modifies.
Wymaga to usilnych starań.
It requires persistent efforts.
Here, 'usilnych' indicates the intense and careful nature of the searches, showing dedication.
Były to wyniki usilnych poszukiwań.
These were the results of diligent searches.
In this sentence, 'usilnych' characterizes the assurances as being made earnestly, emphasizing their sincerity.