Examples: cartography card archaeology archetype monarchy legal loyal purse personal cinema kinase car carpenter hippopotamus Mesopotamia dative data date
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Luxembourgish kafen
German kaufen (cognate)
Proto-West Germanic *kaupōn (inherited)
Old High German koufōn (inherited)
Icelandic kaupa (cognate)
Latin caupo (derived)
Dutch kopen (cognate)

Luxembourgish verkafen (affix)