Feliz, or contento (means content) Feliz and contento/a (depending on the gender of the person who is happy - a for girls, o for boys) both mean happy in Spanish. One could say I'm happy either of these ways: Estoy contenta. Estoy feliz.
feliz
You say, "gemelos."
I'm happy too in Spanish is Estoy contento también.
You can say los chicos for the boys, and las chicas for the girls.
Estamos contentos.
hola chicos
Nothing, that's in English. But if you meant to say HOW to say teenage boys, then its "adolescentes"
You mean "Happy Valentine's Day"?
Happy land in Spanish is tierra feliz. Happy land in Italian is terra felice. Happy land in French is terre heureuse.
Feliz Navidad.
Feliz Navidad!