Caddo is a Native American language, the traditional language of the Caddo Nation. It is critically endangered, with no exclusively Caddo-speaking community and only 25 speakers as of 1997 who acquired the language as children outside school instruction. Caddo has several mutually intelligible dialects. The most commonly used dialects are Hasinai and Hainai; others include Kadohadacho, Natchitoches and Yatasi. Linguistic connections Caddo is linguistically related to the members of the Northern Caddoan language family; these include the Pawnee-Kitsai (Keechi) languages (Arikara, Kitsai, and Pawnee) and the Wichita language. Kitsai and Wichita are now extinct, and Pawnee and Arikara each have fewer surviving speakers than Caddo does. Another language, Adai, is postulated to have been a Caddoan language while it was extant, but because of scarce resources and the language's extinct status, this connection is not conclusive, and Adai is generally considered a language isolate. Use and language revitalization efforts The Caddo Nation is making a concentrated effort to save the Caddo language. The Kiwat Hasí꞉nay ('Caddo Home') foundation, located at the tribal home of Binger, Oklahoma, offers regular Caddo language classes, in addition to creating dictionaries, phrase books, and other Caddo language resources. They have also made a long-term project of trying to record and digitally archive Caddoan oral traditions, which are an important part of Caddo culture. As of 2012, the Caddo Nation teaches weekly language classes; language CDs, a coloring book, and an online learning website are also available. As of 2010, a Caddo app is available for Android phones. There is a Caddo grammar, published August 2018, and an in-depth examination of the Caddo verb, published in 2004. Phonology Consonants Caddo has 19 contrastive consonants, a normal-sized consonant inventory. It is somewhat unusual in that it lacks liquid consonants. The IPA symbols for the consonants of Caddo are given below: Caddo also features contrastive gemination of consonants, which is generally indicated in orthography by a double letter: /nɑ́ttih/ "woman." Vowels Caddo has three contrastive vowel qualities: , and , and two contrastive vowel lengths, long and short. However, there is a great deal of phonetic variation in the short vowels. The high front vowel is generally realized as its lower counterpart , and the high back vowel is similarly often realized as its lower counterpart . The low central vowel has a wider range of variation, pronounced (most commonly) as when it is followed by any consonant