The US government's take on it.
conventional long form: Argentine Republic
conventional short form: Argentina
local long form: Republica Argentina
local short form: Argentina
yes, you're right, almost all adjective changes with gender and number of the object for example: un niño argentino, dos niños argentinos or una niña argentina , dos niñas argentinas. in english it would be one argentinian boy, two argentinian boys or one argentinian girl , two argentinian girls. Hope you understand
In Spanish, the "b" and "v" are not really distinguishable.
They are pronounced the same, but one is "hard" and one is "soft"
It is an anglicismo to pronounce them differently
In Mexico, it is more common for there to be a separate sound, because of the influence of English.
+1 for making me chuckle.
Like Jueveshuevos stated 'b' and 'v' sound practically the same in [Castillo] Spanish. It can be a bit difficult at first but with time and enough practice you'll get the hang of it.
I haven't completely mastered how to distinguish between them but I get it about 80% of the time. There is no way I'm mixing the two in my pronunciation though. I've already got enough problems mixing 'b' and 'p' in my writing.
One in Spanish is uno. However, the trailing 'o' is dropped when it is being used as a quantifier (to indicate the number of items there are).
When this is done, uno, which has now un, cannot be easily distinguished from the indefinite article un. Luckily, there is no explicit requirement for a differentiation between the two because "I want one book" (querio un libro) and "I want a book" (querio un libro) mean essentially the same thing; I do not mind which book it is, I just want one.
The same applies for the sentence we're asked to translate there. Tengo un caballo argentino can mean either "I have an Argentine¹ horse" or "I have one Argentine¹ horse". They both convey the same message.
¹ As a matter of personal preference, I use Argentine instead of Argentinian. You can use either one that suits you best sincce they are both correct and acceptable.
It is the word that comes after the article that determines if we use 'a' or 'an'.
In this case, the word is Argentinian, which starts with a vowel sound. If it was a different word which started with a consonant sound, like Spanish for example, then the article would have been 'a'.