Examples: cartography card archaeology archetype monarchy legal loyal purse personal cinema kinase car carpenter hippopotamus Mesopotamia dative data date
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Cornish penn
← Proto-Brythonic *penn (inherited)
← Proto-Celtic *kʷennom (inherited)

→ Cornish pennskol (prefix)
→ Cornish pennscol (prefix)
→ Cornish pennseythen (prefix)
→ Cornish pednseythen (prefix)
→ Cornish pedncita (prefix)
→ Cornish penncita (prefix)