En is a Kra language spoken in Vietnam. Before its discovery in 1998, En language was undistinguished from Nùng, which is a Central Tai language closely related to Zhuang

Standard Zhuang

The standard Zhuang language is the variety of Zhuang spoken in Wuming County in the Guangxi Zhuang Autonomous Region of the People's Republic of China, where it is an official language.-Classification:...

. In the late 1990s, Vietnamese linguist Hoàng Văn Ma had first recognized that it was not a Tai language, ultimately leading to field work distinguishing En as a separate language. Researchers have determined En to be most closely related to the Buyang language

Buyang language

Buyang is a Tai–Kadai language spoken in Guangnan and Funing counties, Yunnan Province, China by the Buyang people. It is important to the reconstruction of Austro-Tai as it retains the disyllabic roots characteristic of Austronesian languages. Examples are "to die", "eye", "head", and "eight"...

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The speakers of En live in northern Vietnam near the border with Jingxi County

Jingxi County

Jingxi County is a county of Guangxi, China. It is under the administration of Baise city....

, Guangxi

Guangxi

Guangxi, formerly romanized Kwangsi, is a province of southern China along its border with Vietnam. In 1958, it became the Guangxi Zhuang Autonomous Region of the People's Republic of China, a region with special privileges created specifically for the Zhuang people.Guangxi's location, in...

. In 1998, En speakers were found in Nội Thun village, Hà Quảng District, Cao Bằng Province

Cao Bang Province

Cao Bằng is a province of northeastern Vietnam. The province has borders with Hà Giang, Tuyên Quang, Bắc Kạn, and Lạng Sơn provinces within Vietnam. It also has common international border with Guangxi province of the People's Republic of China...

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