Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Silesian
ciynżki
←
Czech
těžký
(cognate)
←
Polish
ciężki
(cognate)
←
Proto-Slavic
*tęžьkъ
(inherited)