The first two are not productive now in normal Spanish words: they are only used in old spellings that have irregularly been retained, and in loanwords from indigenous languages. But they do exist.
Xenofobia is an s, yes, and excursión is "ks" In fsct, Méjico is the traditional way to write Mexico in Spanish grom Spain until it was accepted the other form a few years ago. I still write "Méjico" myself.
And anyway, as you point out, even in Spain the form México is accepted now.
After all, it is where they come from originally and have their own spelling (colour vs color, etc.)
An x in standard spanish has always been the two sounds I told you and that mexican deviation is specific to Mexico.
Yes, it is over 100 million speakers but I was still assuming the root language in its original place as the reference. Sorry if I did not express it correctly.
The "root language spoken in its original place" absolutely did pronounce X like modern J.
"ll" in standard spanish is a strong english "y".
However, in spanish argentinian from the area of Buenos Aires (but not the argentinian Córdoba, which sounds more like colombian spanish) it is "sh", being that s something like a mix in-between of "j" and "s" + h as in "she" but the sound is a bit different.
Without being able to record some sound I cannot express it better but I am sure you can find something around. Javier Milei, the president, has such an accent.
In the last 40 years I've spent mostly in the USA I rarely have heard Uruguayan/Argentinian Spanish in person or in media, but was surprised to hear Messi and others in recent interviews use SH as in "puSH" for the Y/LL, this apparent has been a generational shift in that area, first in Argentina and then Uruguay. I'd sound old-fashioned if I were to go back to Montevideo these days.
In any case, her point wasn't to give a lecture on linguistics, but to impress upon the parents how complicated English really is to learn to read.
This isn't entirely correct. A distinct sound that the mouth makes is a "phone". A phoneme is almost always a group of several phones - allophones - that native language speakers perceive as a single sound. Another way to phrase it is that if you change one phoneme to another one, it makes a different word (possibly a non-existing one, but regardless the native speakers would consider it distinct), but changing from one phone to another doesn't change the word.
For example, in English, the phoneme /t/ has allophones [t], [tʰ], [ɾ], or [ʔ] depending on context. OTOH [ɾ] is a distinct phoneme in Spanish, and [ʔ] is a distinct phoneme in Arabic.
Unfortunately these two are often confused, so one should be careful with such counts and comparing them - it's not uncommon when people count phonemes in their native language, but phones in other languages (when those phones sound distinct to them).
This can also vary significantly from dialect to dialect, since one very common thing in language evolution is for two similar phonemes to collapse into a single one while retaining the original distinction as allophones. For English, in particular, the number of phonemes varies a lot between American and British English (with the latter having more distinctions).
- /k/ can be written both c and qu, and k where it occasionally appears in the language (e.g. kilo) - and the u in qu is silent.
- /s/ can be written c, s, and z, though stress rules are different for c and z.
- r and rr are distinct sounds but r = rr at the beginning of words, I think.
- At least in Mexican Spanish: The "ua" sound can be spelled ua or oa (e.g. Michoacan, Oaxaca) - and also the breathy sound of j can also be written with an x.
- d has a sound a little like English voiced-th at the end of words (e.g. juventud)
The stress rules, to the best of my knowledge, is very systemaic (not 100% but I would say "almost" at least for the words in use). Even the stress rules are very uniform.
> r and rr are distinct sounds but r = rr at the beginning of words, I think.
This is still systematic reading. At the start of a word it is the strong one, yes. And when it is preceded by a consonant, such as in "enredar" (that is strong r). There is no exception of any kind here.
> d has a sound a little like English voiced-th at the end of words (e.g. juventud)
That is some dialects in some areas. We pronounce a clean d at the end in my area (around Valencia). It is also the correct, standard way to do it for spanish. The other is a deviation existing in León, for example.