1 sentence

1. 他们有自己的口头语言，但没有书面语言。

   tā​men yǒu zì​jǐ de kǒu​tóu yǔ​yán, dàn méi​yǒu shū​miàn yǔ​yán.

   They have their own spoken language but no written language.

   Source: CCMatrix