Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Ukrainian
пе́рший
→
Belarusian
першы
(cognate)
→
Ukrainian
першокласний
(affix)
→
Ukrainian
першість
(affix)