/r/ are considered a speech defect, back variants for (, or ) are widespread in rural Puerto Rican Spanish and in the dialect of Ponce, whereas they are heavily stigmatized in the dialect of the capital San Juan. To a lesser extent, velar variants of are found in some rural Cuban (Yateras, Guantánamo Province) and Dominican vernaculars (Cibao, eastern rural regions of the country). In Paraguay, syllable-final is pronounced as before l or s and word-final position, influenced by a substrate from Native American languages. In Chile, as in Andalusia, the archiphoneme in the sequence is sometimes assimilated to in lower-class speakers, and sometimes in educated speakers. Thus, jornada 'workday' may be pronounced . Additionally, in the Basque-speaking areas of Spain, the uvular articulation for , , has a higher prevalence among bilinguals than among Spanish monolinguals. Pronunciation of x The letter x usually represents the phoneme sequence . An exception to this is the pronunciation of the x in some place names, especially in Mexico, such as and the name itself, reflecting an older spelling (see "Name of Mexico"). Some personal names, such as Javier, Jiménez, Rojas, etc., also are occasionally spelled with X: Xavier, Ximénez, Roxas, etc. and the pronunciation of x is either . A small number of words in Mexican Spanish retain the historical pronunciation, e.g. . There are two possible pronunciations of in standard speech: the first one is , with a voiceless plosive, but it is commonly realized as instead (hence the phonemic transcription ). Voicing is not contrastive in the syllable coda. In dialects with seseo, c following x pronounced is deleted, yielding pronunciations such as for . Adoption of the affricates tz and tl Mexican Spanish and some other Latin American dialects have adopted from the native languages the voiceless alveolar affricate and many words with the cluster (originally an affricate ) represented by the respective digraphs and , as in the names Atzcapotzalco and Tlaxcala. is a valid onset cluster in Latin America, with the exception of Puerto Rico, in the Canary Islands, and in the northwest of Spain, including Bilbao and Galicia. In these dialects, words of Greek and Latin origin with , such as and , are also pronounced with onset : , . In other dialects, the corresponding phonemic sequence is (where is the onset), with the coda realized variously as and . The usual pronunciation of those