Editing Tai languages (section)

===Li (1977)===
[[Li Fang-Kuei]] divided Tai into three sister branches.

{{tree list}}
* '''Tai'''
** [[Northern Tai languages|Northern Tai]]
** [[Central Tai languages|Central Tai]]
** [[Southwestern Tai languages|Southwestern Tai]] (Thai)
{{tree list/end}}

Li's Northern group corresponds to Haudricourt's Dioi group, while his Central and Southwestern groups correspond to Haudricourt's Tai proper. The three last languages in Haudricourt's list of 'Tai proper' languages are [[Tày language|Tho (Tày)]], [[Longzhou Zhuang language|Longzhou]], and [[Nung language (Tai)|Nung]], which Li classifies as 'Central Tai'.

This classification scheme has long been accepted as standard in comparative Tai linguistics. However, Central Tai does not appear to be a [[monophyletic]] group.