"Es una gente encantadora" is actually a mistake. "Gente" is a feminine colective noun, which means that it is singular, the plural would be "gentes" (rarely used though, and usually to refer to "people" as "the people of China and the people of Korea"). If the verb is conjugated by "gente" then the verb has to be in singular. La gente es amable = the people is kind. Now, the problem arises from the fact that in many sentences with "gente", the subject is not "gente" but a different element. Ellos son gente muy agradable. In that sentence the subject is not "gente" but "ellos". In your sentence "es una gente encantadora", "gente" is not the noun conjugating the verb "ser", the noun is "ellos". You can find more examples in the following website. http://castellanosindudas.blogspot.com/2012/10/la-gente-y-la-mayoria-singular-o-plural.html I hope this helps.