* Εξηγήστε μου την έννοια αυτού (Exēgēste mou tēn énoia aftou): This is a fairly literal translation. "Εξηγήστε" (Exēgēste) is the polite imperative of "εξηγώ" (exēgō) - to explain. "μου" (mou) means "to me," "την" (tēn) is the definite article "the" (feminine singular), "έννοια" (énoia) means "meaning," and "αυτού" (aftou) means "of this" (masculine singular). This works well for a formal setting.
* Εξηγήστε μου τι σημαίνει αυτό (Exēgēste mou ti simenei auto): This translates to "Explain to me what this means." "τι" (ti) means "what," and "σημαίνει" (simainei) means "means." This is a more natural and less formal option.
* Δώστε μου μια εξήγηση για αυτό (Dose mou mia exēgēsi gia auto): This translates to "Give me an explanation for this." "δώστε" (dose) is the polite imperative of "δίνω" (dīnō) - to give. "μια εξήγηση" (mia exēgēsi) means "an explanation," and "για" (gia) means "for." This is a good choice if you want to emphasize the act of providing an explanation.
The best choice depends on the context. For everyday conversation, the second option is likely the most natural. For a more formal setting, such as a lecture or academic paper, the first option might be preferred. The third option is suitable if you want a slightly more indirect phrasing.