Examples: cartography card archaeology archetype monarchy legal loyal purse personal cinema kinase car carpenter hippopotamus Mesopotamia dative data date
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Bulgarian о-

Bulgarian оток (affix)
Bulgarian оръжие (prefix)
Bulgarian ближа (prefix)
Bulgarian беся (prefix)
Bulgarian овраг (prefix)
Bulgarian огорча (prefix)
Bulgarian обожавам (confix)
Bulgarian оставя (prefix)
Bulgarian опитам (affix)
Bulgarian окажа (affix)
Bulgarian оръдие (prefix)
Bulgarian оженя (affix)
Bulgarian означа (affix)
Bulgarian огледам (affix)
Bulgarian освободя (affix)
Bulgarian освобождавам (affix)