Explanation

Only the consonants [m] and [n] receive tone marks in Yoruba. These nasal sounds can carry tones by themselves because they can form syllables alone.

Other consonants cannot take tone marks. They always appear with vowels. But [m] and [n] are special syllabic consonants that work like vowels.

This unique feature makes Yoruba different from many languages. Knowing which consonants take tones helps you write correctly.