answer:I think the differences you’re noticing in pronunciation are simply due to accents. If you were in the US, the vowels would sound slightly different. I say “back” with the same “a” as in “apple.” I believe it’s the short A sound – if I remember correctly from elementary school. Oh, and apart from variations in accents, the speakers of a language never really speak like they teach in school. Learning Spanish in high school or even college won’t really prepare you much if you’re ever in Mexico, because they speak in a variation of Spanish that includes more slang that you’ll never learn in school. Teachers instruct on how to speak the language properly, but the language isn’t always spoken properly by native speakers.