Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Breton
e
←
Proto-Brythonic
*ɨn
(inherited)
←
Proto-Celtic
*eni
(inherited)
→
Welsh
y
(cognate)
→
Welsh
y
(cognate)