Leco, also written as Leko, is a language isolate that, though long reported to be extinct, is spoken by 20–40 individuals in areas east of Lake Titicaca, Bolivia.

[5][6] Jolkesky (2016) notes that there are lexical similarities with the Kulle, Omurano, Taushiro, Urarina, Arawak, Cholon-Hibito, Jaqi, and Quechua language families due to contact.

[7] Apart from some brief lists of vocabulary, the main document for which Leco is known is a Christian doctrine compiled by the missionary Andrés Herrero at the beginning of the 19th century.

That work was virtually the only available document about Leco, until the linguist Simon van de Kerke (1994) located some speakers of the language and compiled some additional facts which enlarged the analysis of Quevedo.

In regard to the characteristics of spoken Leco, one can point out the following: hinothisyobas-neman-TOPpalantaplatanosoh-cha-no-telook at-PR-NML-DCLmoki-aGEN-3choswai-kiwife-DAThino yobas-ne palanta soh-cha-no-te moki-a choswai-kithis man-TOP platano {look at-PR-NML-DCL} GEN-3 wife-DAT‘This man is searching for platano for his wife (of another).’ Unknown glossing abbreviation(s) (help);cherawedu-kama-teanspeak-can-1PLBuruaLekoda-in-teanwant-NEG-1PLdu-chspeak-INFchera du-kama-tean Burua da-in-tean du-chwe speak-can-1PL Leko want-NEG-1PL speak-INF'We can speak Leco, but we do not want to speak it.aychameatne-no-teexist-NML-DCLaycha ne-no-temeat exist-NML-DCL‘There is meat!’ Unknown glossing abbreviation(s) (help);wesraGuanaynosfarna-in-tha-tebe-NEG-DIM-DCLwesra nos na-in-tha-teGuanay far be-NEG-DIM-DCL‘Guanay is very near.’ Unknown glossing abbreviation(s) (help);sok’ochfoodda-no-newant-NML-INTiya-nyou.SG-INTsok’och da-no-ne iya-nfood want-NML-INT you.SG-INT‘Do you (singular) want to eat?’ Unknown glossing abbreviation(s) (help);ha-newho-INTbusa-cha-no-narrive-PRS-NML-INTha-ne busa-cha-no-nwho-INT arrive-PRS-NML-INT‘Who is arriving?’ Unknown glossing abbreviation(s) (help);onthatchelas-nobecome sick-NMLyobas-neman-TOPk’o-in-teeat-NML-DCLwet-ra-no-tedie-FUT-DCLon chelas-no yobas-ne k’o-in-te wet-ra-no-tethat {become sick-NML} man-TOP eat-NML-DCL die-FUT-DCL‘That sick man is not eating; he is going to die.’ Unknown glossing abbreviation(s) (help);onthatchelas-nobecome sick-NMLk’o-in-teeat-NML-DCLnonotko-in-tedrink-NML-DCLwet-ra-no-tedie-FUT-DCLon chelas-no k’o-in-te no ko-in-te wet-ra-no-tethat {become sick-NML} eat-NML-DCL not drink-NML-DCL die-FUT-DCL‘That sick man is neither eating nor drinking; he is going to die.’ Unknown glossing abbreviation(s) (help);ch’epeillyin-soncho-a-ra1.BEN-become sick-PF-LOCkatre-tecot-LOCbar-ka-cha-no-to:lying-AUX-PRS-NML-PRS.1ch’epe yin-soncho-a-ra katre-te bar-ka-cha-no-to:ill {1.BEN-become sick-PF-LOC} cot-LOC lying-AUX-PRS-NML-PRS.1‘Because I feel ill I am lying on a cot.’ Unknown glossing abbreviation(s) (help);In regard to the lexicon and the classes of words in Leco, one can mention the following (van de Kerke, 2009: 293–297): Loukotka (1968) lists the following basic vocabulary items for Leco.