Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Catalan
oportú
←
Latin
opportūnus
(derived)
→
Catalan
oportunista
(affix)
→
Catalan
oportunisme
(affix)