Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Istro-Romanian
påtru
←
Proto-Indo-European
*kʷetwóres
(inherited)
←
Latin
quattuor
(inherited)
←
Romanian
patru
(cognate)