Examples: cartography card archaeology archetype monarchy legal loyal purse personal cinema kinase car carpenter hippopotamus Mesopotamia dative data date
...
Vietnamese lòn
Proto-Mon-Khmer *lɔːn (inherited)
Proto-Mon-Khmer *lun (inherited)
Proto-Mon-Khmer *luən (mention)
Proto-Mon-Khmer *lən (mention)
Vietnamese luồn (link)