Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Breton
ha
←
Proto-Brythonic
*(h)a
(inherited)
←
Welsh
a
(cognate)
←
Welsh
ag
(mention)
←
Proto-Indo-European
*ad-gʰe
(inherited)
←
Cornish
ha
(cognate)
→
Cornish
ha
(cognate)