Kwʼadza is poorly attested, and its grammar was never recorded in detail. Regardless, the marking of gender and number on nouns, as well as what appear to be derivational suffixes on attested nouns and verbs, can be consistently connected with the other Rift languages. While Kwʼadza is accordingly agreed to be a South Cushitic language, its classification within the group is not certain. Fleming and Ehret proposed that Kwʼadza would form a subgroup with
Asa, called "East Rift" by the latter. Ehret proposes a set of shared East Rift sound changes, including e.g. a merger of Proto-Rift
pharyngeals *ħ and *ʕ with the
glottals *h and *ʔ, respectively, and a merger of a Proto-Rift central vowel *ɨ into either *e or *o depending on the consonant environment. Kruijsdijk (2024) instead argues that Kw'adza is closer to West Rift than to Asa, being the second to split off from West Rift. Blažek (2019) proposes, using a glottochronological analysis, that Kw'adza was the first to split off from West Rift, though notes that some figures may not be reliable due to later influence, i.e. of Burunge on Alagwa. The known lexicon of Kwʼadza has a large stock of identifiably Rift / South Cushitic roots, as well as loanwords from other languages from the area, as also in the other Rift languages. The non-Cushitic numerals
itame 'one' and
beʼa ~ mbɛa 'two' suggest a connection with
Hadza, while e.g.
haka 'four' (found also as Asa
hak and
Mbugu háí) suggests a connection with
Sandawe and the
Khoe languages. Ehret notes as distinctively East Rift lexicon, shared only by Kʼwadza and Asa, the following: == Phonology ==