words in most of Spain is and . The sound also occurs in European Spanish in loanwords of Basque origin (but only learned loanwords, not those inherited from Roman times), as in abertzale. In colloquial Castilian it may be replaced by or . In Bolivian, Paraguayan, and Coastal Peruvian Spanish, also occurs in loanwords of Japanese origin. Other loaned phonetics Spanish has a fricative for loanwords of origins from native languages in Mexican Spanish, loanwords of French, German and English origin in Chilean Spanish, loanwords of Italian, Galician, French, German and English origin in Rioplatense Spanish and Venezuelan Spanish, Chinese loanwords in Coastal Peruvian Spanish, Japanese loanwords in Bolivian Spanish, Paraguayan Spanish, Coastal Peruvian Spanish, Basque loanwords in Castilian Spanish (but only learned loanwords, not those inherited from Roman times), and English loanwords in Puerto Rican Spanish and all dialects. Pronunciation of ch The Spanish digraph ch (the phoneme ) is pronounced in most dialects. However, it is pronounced as a fricative in some Andalusian dialects, New Mexican Spanish, some varieties of northern Mexican Spanish, informal and sometimes formal Panamanian Spanish, and informal Chilean Spanish. In Chilean Spanish this pronunciation is viewed as undesirable, while in Panama it occurs among educated speakers. In Madrid and among upper- and middle-class Chilean speakers, it can be pronounced as the alveolar affricate . Open-mid and open front vowels In some dialects of southeastern Spain (Murcia, eastern Andalusia and a few adjoining areas) where the weakening of final leads to its disappearance, the "silent" continues to have an effect on the preceding vowel, opening the mid vowels and to and respectively, and fronting the open central vowel toward . Thus the singular/plural distinction in nouns and adjectives is maintained by means of the vowel quality: libro 'book', but libros 'books'. libre 'free, singular ', but libres 'free, plural'''. libra 'pound', but libras 'pounds'. Furthermore, this opening of final mid vowels can affect other vowels earlier in the word, as an instance of metaphony: lobo 'wolf', but lobos 'wolves'. (In the remaining dialects, the mid vowels have nondistinctive open and closed allophones determined by the shape of the syllable or by contact with neighboring phonemes. See Spanish phonology.) Post-tonic e and o Final, non-stressed and may be raised to and respectively in some rural areas of Spain and Latin America. Examples include 'night', . In Spain, this is mainly found in Galicia and other northern