Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Old Church Slavonic
сълати
←
Proto-Slavic
*sъlati
(inherited)
→
Old Church Slavonic
посълати
(prefix)
→
Ukrainian
посольство
(cognate)