Examples: cartography card archaeology archetype monarchy legal loyal purse personal cinema kinase car carpenter hippopotamus Mesopotamia dative data date
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Esperanto agi
French agir (borrowed)
Italian agire (borrowed)

Esperanto agema (suffix)
Esperanto kontraŭagi (affix)
Esperanto reagi (affix)
Esperanto agigi (affix)
Esperanto agado (suffix)
Esperanto agadi (affix)
Esperanto interagi (affix)
Esperanto kunagi (affix)
Esperanto agmaniero (affix)
Esperanto agmetodo (compound)