Bongo language

Bongo (Bungu), also known as Dor, is a Central Sudanic language spoken by the Bongo people in sparsely populated areas of Bahr al Ghazal in South Sudan.

Vowels
Bongo has ten vowel qualities, which can be long or short.

Bongo also has vowel harmony. The "heavy" vowels, written with diaereses, contrast with the "light" vowels.

Tone
Bongo is tonal language that has the high (á), mid (ā), low (à) and falling (â) tones.

All falling tones occur on either long vowels or on vowel clusters or glides. When the tonal fall is not due to a preceding high tone, it can be indicated by a high tone followed by a low tone.

Numerals
Bongo has a quinary-vigesimal numeral system.

Scholarship
The first ethnologists to work with the Bongo language were John Petherick, who published Bongo word lists in his 1861 work, Egypt, the Soudan, and Central Africa; Theodor von Heuglin, who also published Bongo word lists in ''Reise in das Gebiet des Weissen Nil, &c. 1862-1864 in 1869; and Georg August Schweinfurth, who contributed sentences and vocabularies in his Linguistische Ergebnisse, Einer Reise Nach Centralafrika'' in 1873. E. E. Evans-Pritchard published additional Bongo word lists in 1937.

More recent scholarship has been done by Eileen Kilpatrick, who published a phonology of Bongo in 1985.