Donor Kra

Kra branches contain many non-Sinitic words that are of Sino-Tibetan origin, but these words cannot be traced to any known branch of Sino-Tibetan. Hence, I have posited a "missing" "Donor Kra" branch.

Negation patterns and possibly also sesquisyllabic patterns in Kra were borrowed from Donor Kra.

Tibeto-Burman loanwords in Proto-Kra

No particular Tibeto-Burman branch can be identified as the source of the Kra loanwords. Tibeto-Burman loanwords appear to have been borrowed very early into Kra.

Kra negators were also borrowed from Tibeto-Burman.

DeLancey (2007) notes that Proto-Kuki-Chin has the postverbal negators *law, #kay, and *no.

Among Tibeto-Burman languages in southwestern China, I believe post-verbal is only found in Tujia. To my knowledge, no Lolo-Burmese has it, but it is common in Tibeto-Burman languages of Northeast India, including languages of the Kuki-Chin-Naga area and other nearby Tibeto-Burman branches. (See WALS Atlas Feature 143A: Order of Negative Morpheme and Verb)

This points to the possibility of a previously existent ("missing") Tibeto-Burman branch in northern Guangxi / Guizhou-Guangxi border region that had influenced the typology of early varieties of Kra. This "missing" branch, which I will call "Donor-Kra," would have been an independent branch of Sino-Tibetan that was in the same linguistic area as Tujia. Donor-Kra would have been subsequently absorbed by Kra, Hmong-Mien, Sinitic, and other languages in the Guangxi-Guangxi border region.