Kadiwéu is a Guaicuruan language spoken by the Kadiweu people of Brazil, and historically by other Mbayá groups.
Linguist Filomena Sandalo, who worked with the Kadiweu people for a couple of years, offers an extensive analysis of the morphological components of the language.
However, in 1968 the Griffiths partnered with SIL (Sociedade Internacional de Lingüística), which led to the documentation of the Kadiweu language.
Their book Aspectos da Língua Kadiweu discussed the formation and grammatical structure of the language.
Moreover, an influential source according to Povo Indigenas no Brazil is the 18th-century ethnographic account of Kadiwéu by F. José Sanchez-Labrador.
This is due to the penetration of cattle farmers into the original Kadiwéu lands, which were gained by fighting and sacrificing their lives.
Kadiweu has interesting linguistic aspects that highlight and distinguish it from other native languages.
The work of linguist Maria Filomena Sandalo, A Grammar of Kadiweu, presents a general description of the language.
This author uses valency change to refer to the syntactically relevant components of meaning specified in the lexicon of Kadiweu.
It is important to note that non-accusative verbs only take an internal argument, and within their semantics is something that undergoes a change of state, ([+become]).
[I cause guava (to) become eaten] [9]The third category is trivalent verbs which make an obligatory reference to a third party argument.
[I cause his knife (to) become sharpened] [10]In conclusion, while Sandalo does not explicitly state that this is an increasing valency change, she identifies a causative suffix which is a typical valency-increasing device.
nigenigeCOMPdaGadaGaNEGenagiy-ane-g3SG.SUBJ-come-TLCdom:ojyadom:ojyacarnatiginatiginextnigoy,nigoymorningbGajawaligi.bGa+j-awaligiINCOMPL+1SG.SUBJ-walknige daGa enagi dom:ojya natigi nigoy, bGajawaligi.nige daGa y-ane-g dom:ojya natigi nigoy bGa+j-awaligiCOMP NEG 3SG.SUBJ-come-TLC car next morning INCOMPL+1SG.SUBJ-walk'If the car does not come tomorrow, I will walk away.'
[15]For the sixth and seventh aspects, repetitive and intensive, marked by +ak and +bigi, the author does not explain or go into detail about it.