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Μία χελιδὼν ἔαρ οὐ ποιεῖ → One swallow does not a summer make
κατ' ἐνιαυτόν, πρὸ ἐνιαυτοῦ, τοῦ ἐνιαυτοῦ, ἐνιαύσια, ἐνιαυσίως, ἐνιαυσιαίως