Advance Tongue Root (ATR) in Akan (Twi) Vowels

Akan (Twi) Alphabet has ten (10) vowels. All the ten vowels in Akan (Twi) are represented in Adinkra Alphabet compare to the Latin orthography in which only 7 vowels are represented. There are two subset of vowels in Akan known as +ATR and -ATR. Each subset of vowels contain 5 vowels in Adinkra Alphabet. The phenomenon in which vowels in each subset of 5 occurs together or changes the preceding vowel to a vowel within each subset is known as vowel harmony.