How do word-order patterns differ among Nilo-Saharan languages?

Nilo-Saharan languages exhibit significant typological diversity in word order, reflecting their broad geographic distribution and historical contact with neighboring language groups. These patterns generally fall into two typological extremes:12

• Verb-initial structures: Languages in the eastern zones, including many Nilotic, Kuliak, Kadu, and several Surmic languages, typically place the verb before the subject and object. These languages often feature prepositions and auxiliaries that precede the main verb.1
• Verb-final structures: Western and northern languages, such as Fur, Kunama, and the Maban and Nubian languages, generally place the verb at the end of the sentence. These languages tend to use postpositions and place auxiliaries after the verb.1

Beyond these primary categories, word order can be more flexible. Some Surmic languages allow for relatively free word order, while Central Sudanic languages alternate between verb–object and auxiliary–object–verb structures. Syntactic relations in these languages are often expressed through case-marking suffixes or tonal inflection.1