Try to state as a general rule when to pronounce 'ó' and when 'ô'!
Velar nasal 'ô': after back vowels, like: o, õ, u, ö
Alveolar nasal 'ó': after front vowels resp. non-back vowels, like: i, ò, e, ñ and a
[More on Akan nasals: Dolphyne, 1988: 38-42; 140-143]
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