Tone is the high, low, falling or rising sound of a word. There are five different patterns of tone in Bongo nouns.
|Underlying tone||Surface tone||Number of two syllable nouns|
The tone of a word that we hear is called its surface tone. The surface tone of a word changes according to the tone of other words in the sentence. Each word also has underlying tone. This is the original tone assigned to a word which can be different than the tone we hear. The underlying tone of a word is the same in every sentence, but the surface tone of a word can change from one sentence to the next. In the dictionary, the surface tone of nouns is given in-between brackets such as maya [mꜜáyá] yam, and the underline tone is shown in the tone field (of the non-printed dictionary) as letters such as LHL.