Nouns are substantive or adjective, and have number, gender, and case.

Singular and Plural.—Nouns terminating in a short, or unaccented vowel, add an s for the plural; as, boy, muchacho; boys, muchachos. Nouns ending in an accented vowel, or in a consonant, or in y, add es to the singular; as, ruby, rubí; rubies, rubíes; lion, leon; lions, leones; ox, buey; oxen, bueyes. Nouns terminating in z, change it into c to form the plural; as, cross, cruz; crosses, cruces.