Examples: cartography card archaeology archetype monarchy legal loyal purse personal cinema kinase car carpenter hippopotamus Mesopotamia dative data date
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Russian учиться
Old East Slavic учити (inherited)
Old East Slavic сѧ (mention)
Russian учи́ть (affix)
Russian -ся (affix)
Proto-Slavic *učiti (derived)
Proto-Slavic *sę (mention)