Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Breton
tri
←
Proto-Brythonic
*tri
(inherited)
←
Proto-Celtic
*trīs
(inherited)
←
Proto-Indo-European
*tréyes
(inherited)
→
Breton
trizek
(compound)
→
Breton
triwec'h
(compound)
→
Breton
tri-ugent
(compound)