Tú eres/usted es loco/a = you are (informal, singular/formal, singular) crazy (male/female) by nature.
Tu estas/ustedes estan locos = you are (informal plural/formal, plural) are crazy (at the moment)
(Above answer is incorrect.)
las personas son locas = people/persons are mad.
la gente es loca = folk/people are mad.
loco
Bésame el trasero that's how u say you are crazy about me
You can say "Estoy loco(a)".
¿Eres loco?
Estamos locos
Me vuelves loco/a.
No estoy loco
You say, "tortuga loca."
You could say "Sombrero loco".
no demente, desquisiado, son others ways to say crazy.
"piernas locas"
hermana loca