Both «отчего» and «почему» translate to “why?” in English, but they differ in style, usage, and grammatical behavior . Here's a clear breakdown: 🔹 1. Meaning & Core Difference Word Literal Meaning Common Use Почему “For what reason?” Neutral, standard way to ask “why?” in modern Russian. Used in all contexts (spoken, written, formal, informal). Отчего “From what?” / “Due to what?” More literary, old-fashioned, or poetic . Often implies cause or origin (like “what caused this?”). Rare in everyday speech. ✅ In 99% of everyday situations , use почему . 📚 Отчего appears in literature, poetry, proverbs, or for stylistic effect. 🔹 2. Grammatical Behavior Both introduce why-questions , but they govern different cases in the answer (though this is often invisible in simple sentences): Почему → usually answered with prepositional phrases or clauses ...