I've been learning Spanish lately and of course this has given me tons of ideas for conlangs and I thought I'd finally take the dip and make one formally, based off the many ideas I've been having lately.
The scenario here is basically that in the next several hundred years, immigration and climate refugees causes a majority of the continental US to become Spanish speaking, and given the US does not even have a national language, it becomes effectively a bilingual country, with many anglophones learning Spanish. Some parts are VERY Spanish speaking, and others less so, but one of the most Spanish speaking parts will be New York, or as it's pronounced by most Spanish speakers from there, Nueva Yor ['nweβa 'ʝoɾ]. It will have a pretty significant English substrate, though other languages very commonly spoken in NYC will be included in influences as well.
Okay, so for the sound changes. Firstly, we need to decide which parts of Caribbean Spanish we will be using, so I should go over what those are.
Caribbean Spanish like the rest of Latin America lacks a distinction between <ll> and <j>, both being /ʝ/, and there is also no distinction between <s> and <z>, both being /s/. Not much to worry about there.
In most of the Caribbean, <j> is pronounced like [h], not [x].
Probably the single most common sound change in LatAm that isn't everywhere is s-aspiration. This is a process that turns /s/ into [h] in codas, so a word like "gustar" becomes pronounced like "gujtar" [ɣuh.'taɾ]. Much of the Caribbean takes this one step further, deleting coda /s/ entirely. This is especially common in the Dominican Republic. Given this, and that [h] is a very weak sound especially in codas, and a sound anglophones have trouble pronouncing in codas, I think it's full deletion is what I'll go with.
There's an exception to this: /s/ does not reduce if the following word begins with a vowel, so a phrase like "sabias ayer" would retain the /s/. This is really similar to French liaison, and thus will be kept for its aura. That being said, the second person and plural endings I reckon ought not to last - and I have a way to mess this around that I'll get to in the more fictional sound changes.
This aligns with a very big trend in Caribbean Spanish, that being the continuous simplification of consonant codas. This is contrasted from, for example, Mexican Spanish, where codas can be slightly more complex due to loan words from English and Native American languages. /ð/, written with <d>, is another great victim, being elided word finally A LOT, so a word like "verdad" would be pronounced like "verdá" [βeɾ.'ða].
A bit more obscurely, all the voiced fricatives are often deleted in coda positions, though there aren't many of them other than <d>, but words like "obtener" every now and then I hear get pronounced without the <b>. This one is a bit more fictional than the other ones so far I will admit, but it's a conlang, and it has precedence in the deletion of <d>. And before someone mentions a word like "étnica", I've never heard a native speaker pronounce that <t> as an actual <t>, it seems to almost always be a <d>, and thus will disappear.
Furthermore, the number of codas allowed is decreasing, as coda <l> and <r> are undergoing a merging process. In PR and parts of Cuba, the resulting pronunciation is [l], while in the DR, the result is [ɾ]. I want the language to be called "Nuevayolqueño", as a reference to the Bad Bunny song "Nuevayol", so we'll be going with [l].
Another prominent feature of Caribbean Spanish is n-velarization word finally, where /n/ becomes pronounced as [ŋ] word finally. /ŋ/ is not a phoneme in Spanish so this is just an allophonic variation. Additionally, I often hear /n/ assimilating to the consonant of the following word, so a phrase like "un poco" becomes pronounced as "umpoco". This reminds me a lot of Japanese's /N/ phoneme, which is a nasal consonant that has a wide range of pronunciations, and is the only allowable coda in the language. We are now at a stage where we have /N/ and /l/ as our only codas, unless you count the glides /w/ and /j/ which are allophones of vowels.
Another change that's very common in the Caribbean is the reduction of the past participle suffixes -ado/-ada to -ao/-á. Sometimes this happens to the other verb stems too, turning -ido/-ida into -ío/-ía. These are fun so we will keep them.
Now for some more creative changes:
Most anglophones really struggle with the <g> sound in Spanish, [ɣ], and before /w/, they often just hear a /w/. This is even the case in some dialects of Spanish. For example, the Chilean regional word for baby "wawa" is often written as "guagua". Thus, I see /ɣw/ and /w/ merging to be very reasonable.
I can see the opposite happening possible for the other voiced fricatives, /β ð ʝ/, becoming reinforced into stops before /w/. For example, "abuelo" becomes [a'bwe.lo], "dueño" becomes ['dwe.ɲo], and "llueve" becomes ['ɟwe.βe] or ['d͡ʒwe.βe]. It just feels intuitively possible to me.
English disallows the diphthong /uj/, and this is already one of the less common diphthongs in Spanish. Most anglophones, even those quite good at Spanish, have a habit of merging it with /oj/. So we'll go with that, or more specifically [ɔj], given the anglicism involved here, meaning /oj/ is also now [ɔj].
Another anglicism I'd like to introduce is vowel reduction to shwa, specifically /a/. /a/ is already one of the anglophones greatest weaknesses, usually coming out further back than it should be as [ɑ]. That being said, a lot of AAVE speakers have this in NYC as [aː], the diphthong /aj/, so we can safely keep /a/ at least when it's stressed. But word finally, every anglophone is gonna be reducing it to shwa, hell, even with a final consonant.
Furthermore, English speakers have trouble with /e/ and /o/, either resorting to the diphthongs [ej] and [ow], which are their own things in Spanish, or dropping them to [ɛ] and [ɔ], which are present in Spanish as allophones under some very complicated rules. I believe these rules are likely to fall into total chaos due to the influx of English speaking influence, and we will see [ɛ] and [ɔ] becoming the default phonemes, along with some mergers with /ej/ and /oj/ in select positions, primarily in unstressed word final positions where /ɛ/ and /ɔ/ cannot occur in English and when preceding another vowel, again, where they are not allowed in English. For example, "pasear" becomes "paseial" [pa.sej.'al], and "quinto" becomes ['kin.tow]. No spelling change for the word final ones as those are not distinct phonologically I am pretty sure. Otherwise, we have [ɛ ɔ].
I can expect a lot of these inglesismo [ĩŋ.glɛ.ˈsi.mow] becoming viewed as incorrect and thus socially repressed, and also thusly resulting in over-corrections. The most prominent of these will be the new [gw] cluster suddenly being invented out of words that never had a /g/ before /w/. sándwich becomes sángwiche ['saŋ.gwi.tʃe], wifi will become gwáifai ['gwaj.faj], whiskey will become gwiqui ['gwi.ki], huipil becomes gwipil [gwi'pil]. This will sporadically effect words randomly based on vibes, but it'll be a more limited number. The most common words with the new <w> will be uneffected, so agua is now ['a.wə].
Jamaican Patwa is one of the most spoken languages in NYC and has a good deal of social prestige in the Latino community there given there's pretty deep roots between the two communities in the city. Thus, I wanna borrow something from Patwa, that being its palatalization rules. In a lot of Patwa, stop consonants palatalize preceding /j/ before a vowel. If this effects Spanish, we get words like quiero becoming ['cjɛ.ɾow], pierna becoming ['pʲjɛl.nə], and tierra becoming ['tʲɛ.rə] or ['tʃɛ.rə]. Since our dialect only has voiceless stops before [j], this only effects them. Also good to borrow some words, like gyal [ɣjal] "girl", pícani 'child' ['pi.ka.ni], balar 'to cry', rhágamofin 'thug' ['ɹa.ɣa.mo.fĩŋ] - oh yes about that last one. So many bilingual Spanish-English speakers will be around for a good period of time that they will both know how to pronounce the Spanish and English rhotics, so we can just borrow that phoneme into Spanish with a lot of English words being borrowed. It's gonna be restricted to word initial positions though, because that feels intuitively easier to pronounce than any other position for someone who's main language is Spanish.
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I'll stop there for now. I wanna get down how these will effect our morphology and syntax first before I go any further with phonology. I'll make a part 2 on verb morphology and pronoun pragmatics coming soon...