Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Czech
tuhý
←
Proto-Slavic
*tǫgъ
(inherited)
→
Czech
tuhnout
(affix)
→
Slovene
tog
(cognate)
→
Silesian
tyngi
(cognate)