With Czech language you can give three variants to {{PLURAL}} template:
{{plural:$1|kategorie|kategorie|kategorií}}
The same should be in Polish (currently there are only two forms).
KDE handles these three forms with such expression:
n==1 ? 0 : n%10>=2 && n%10<=4 && (n%100<10 || n%100>=20) ? 1 : 2
Version: unspecified
Severity: enhancement