Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Latvian
sērs
←
Proto-Indo-European
*ser-
(derived)
←
Latin
serum
(cognate)
←
Latvian
sērs
(mention)
←
Old East Slavic
-
(cognate)
←
Old East Slavic
сѣр
(mention)
←
Old East Slavic
сѣра
(mention)
←
Russian
се́ра
(cognate)
→
Latvian
sērs
(mention)
→
Latvian
sērskābe
(compound)