may produce vowel nasalization. In these dialects, words such as ('bread') and ('well') may sound like pang and byeng to English-speakers. Velar -n is common in many parts of Spain (Galicia, León, Asturias, Murcia, Extremadura, Andalusia, and Canary Islands). In the Americas, velar -n is prevalent in all Caribbean dialects, Central American dialects, the coastal areas of Colombia, Venezuela, much of Ecuador, Peru, and northern Chile. This velar -n likely originated in the northwest of Spain, and from there spread to Andalusia and then the Americas. Loss of final -n with strong nasalization of the preceding vowel is not infrequent in all those dialects where velar -n exists. In much of Ecuador, Peru, Venezuela (except for the Andean region) and Dominican Spanish, any pre-consonantal or can be realized ; thus, a word like ambientación can be pronounced . R sounds All varieties of Spanish distinguish between a "single-R" and a "double-R" phoneme. The single-R phoneme corresponds to the letter r written once (except when word-initial or following l, n, or s) and is pronounced as , an alveolar flap—like American English tt in better—in virtually all dialects. The single-R/double-R contrast is neutralized in syllable-final position, and in some dialects these phonemes also lose their contrast with , so a word such as may sound like altesanía. This neutralization or "leveling" of coda and is frequent in dialects of southern Spain, the Caribbean, Venezuela and coastal Colombia. The double-R phoneme is spelled rr between vowels (as in carro 'car') and r word-initially (e.g. rey 'king', ropa 'clothes') or following l, n, or s (e.g. alrededor 'around', enriquecer 'enrich', enrollar 'roll up', enrolar 'enroll', honra 'honor', Conrado 'Conrad', Israel 'Israel'). In most varieties it is pronounced as an alveolar trill , and that is considered the prestige pronunciation. Two notable variants occur additionally: one sibilant and the other velar or uvular. The trill is also found in lexical derivations (morpheme-initial positions), and prefixation with sub and ab: abrogado (also pronounced , or ), 'abrogated', subrayar (also pronounced , or ), 'to underline'. The same goes for the compound word ciudadrealeño (from Ciudad Real). However, after vowels, the initial r of the root becomes rr in prefixed or compound words: prorrogar, infrarrojo, autorretrato, arriesgar, puertorriqueño, Monterrey. In syllable-final position, inside a word, the tap is more frequent, but the trill can also occur (especially in emphatic or oratorical style) with no semantic difference,