Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
North Frisian
taag
←
Proto-West Germanic
*þak
(inherited)
←
Old Frisian
thek
(inherited)
→
Saterland Frisian
Täk
(cognate)