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κυσί

Γηράσκω δ᾽ αἰεὶ πολλὰ διδασκόμενος -> I grow old always learning many things
Solon the Athenian

French (Bailly abrégé)

dat. pl. de κύων.

Russian (Dvoretsky)

κῠσί: dat. pl. к κύων.