The Sila speak a Tibeto-Burmese
language, which also makes it Sino-Tibetan. Specifically, it is categorized as:
Lolo-Burmese, Loloish, Southern, Akha, Hani. It
is closely related to Akha, and Hani.
Their language is a completely different language group from Vietnamese,
which is of the Mon-Khmer group.
