Kaiwá language
Kaiwá is a Guarani language spoken by about 18,000 Kaiwá people in Brazil in the state of Mato Grosso do Sul and 510 people in northeastern Argentina. Literacy is 5-10% in Kaiwá and 15–25% in Portuguese. Kaiwá proper is 70% lexically similar with the Pai Tavytera language, and its similarity to its linguistic cousin Guaraní, one of the two national-languages of Paraguay alongside the Spanish language, means it is even sometimes considered mutually intelligible. Provided by Wikipedia
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