Re: Números en inglés (pronunciación)
"Seventy" is distinguished from "seventeen" by the emphasis: seventy vs. seventeen. If someone misunderstands you and you need to clarify, you don't stress the T, which "seventeen" also has, you stress the first syllable more: "No, SEVenty, not sevenTEEN."
I don't know where you're getting the "r" sound. It needs to be harder than that. You're going to sound like you're drunk
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