You should explain that "y'all" is used in the Southern US and in many rural areas. "You guys" is used in informal situations throughout the rest of the country.
Also, it's common in Spanish to use the masculine pronouns as the neuter. However, there's no proper pronoun for the neuter sex in English, although most Americans use "they," "them," or "their," even in the singular.
Note: "they", "them" and "their" is correct as the singular neuter, origionally it was used then the number was unknown.
P.S. I fixed this 02:14 7 abr 2006 (UTC)