Right index finger: raise it to the upper line to play the black keys (sharps), lower it to the lower line for the white keys; move sideways to pick the note (C3–C5, left = low, right = high). Extend more right-hand fingers to play a chord on that note: 1 = single, 2 = major, 3 = minor, 4 = dominant 7th. Left hand openness → volume (fist = silent, spread = full).
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