How do you say good girl in Greek?

There isn't a direct translation of "good girl" in Greek that captures the same nuance. The best way to say it depends on the context and your relationship with the girl. Here are a few options:

* Μπράβο κορίτσι μου (Bravo koritsi mou): This translates to "Bravo, my girl," and is a good option if you want to praise a girl's good behavior. It's affectionate and encouraging.

* Καλή κοπέλα (Kali kopela): This translates literally to "good girl," but sounds a bit more formal and less affectionate than "Bravo koritsi mou." It might sound slightly condescending depending on the tone and context.

* Εξαιρετική (Exairetiki): This means "excellent" or "exceptional," and could be used as a compliment. You could say "Εξαιρετική κοπέλα" (Exairetiki kopela) meaning "excellent girl".

* Αγάπη μου (Agapi mou): This means "my love" and is suitable for a close relationship, expressing endearment rather than simply praising good behavior.

The best choice depends heavily on the context and your relationship with the person. For most situations, "Μπράβο κορίτσι μου" is likely the most appropriate and natural-sounding option.