The tones are divided into two groups with modal and non-modal (tense, harsh or breathy) phonation.
Different scholars have proposed that it is an early offshoot or sister language of Chinese, part of the Loloish branch, or a separate group within the Sino-Tibetan family.
Xu and Zhao (1984) divided Bai into three dialects, which may actually be distinct languages: Jianchuan (Central), Dali (Southern) and Bijiang (Northern).
[5] Jianchuan and Dali are closely related and speakers are reported to be able to understand one another after living together for a month.
The more divergent Northern dialects are spoken by about 15,000 Laemae (lɛ21 mɛ21, Lemei, Lama), a clan numbering about 50,000 people who are partly submerged within the Lisu.
[6] They are now designated as two languages by ISO 639-3: Wang Feng (2012)[10] provides the following classification for nine Bai dialects: Wang (2012)[11] also documents a Bai dialect in Xicun, Dacun Village, Shalang Township, Kunming City (昆明市沙朗乡大村西村).
[13] To determine its origin, researchers must first identify and remove from consideration the various layers of loanwords and then examine the residue.
[37] Lee and Sagart (2008) refined their analysis, presenting the residue as a non-Chinese form of Sino-Tibetan, though not necessarily Loloish.
They also note that this residue includes the Bai vocabulary relating to pig rearing and rice agriculture.
[39] Gong (2015) suggests that the residual layer may be Qiangic, pointing out that the Bai, like the Qiang, call themselves "white", whereas the Lolo use "black".
[48] In a renewed attempt in 1982, language planners used the Jianchuan dialect as a base, because it represented an area with a significant population, almost all of whom spoke Bai.
[49][50] The script was revised extensively in 1993 to define two variants, representing Jianchuan and Dali respectively and has since been more widely used.
[51][52][53] The retroflex initials zh, ch, sh and r are used only in recent loanwords from Standard Chinese or for other Bai varieties.
[60] The Shanhua tablet (山花碑), from Dali Town in Yunnan, contains a poem written using Bowen text from the Ming dynasty by the Bai poet Yang Fu (杨黼),[61] 《詞記山花·詠蒼洱境》.