Traditional Culture Encyclopedia - Traditional festivals - How many of the 55 ethnic minorities in China have no spoken and written languages?

How many of the 55 ethnic minorities in China have no spoken and written languages?

Han, Manchu, Mongolian, Hui, Tibetan, Uygur, Miao, Yi, Zhuang, Buyi, Dong, Yao, Bai, Tujia, Hani, Kazak, Dai, Li, Lisu, Wa, She and Gaoshan.

Daur, Wa, Qiang, Bulang, Salar, Maonan, Gelao, Xibe, Achang, Pumi, Korean, Tajik, Nu, Uzbek, Russian, Ewenki, etc.