it is "Ustedes Estan Locos"
:D
"Vosotros estáis locos" is better, becasuse it's more colloquial.
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I'm not entirely certain, so I'll leave the previous up.
Ustedes estan locos would mean 'You feel crazy', I believe. Sois locos would mean 'You are crazy'.
'Vosotros' is an unnecessary edition, since sois/estáis means 'you are' already. Ustedes estan locos is for talking to strangers/being polite, which would be a bit contradictary in that sentance. :P
So, basically, 'Sois locos'. :P
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.
In Spanish: "Estas loco?". If you're saying it to a girl you say it like this "Estas loca?".
Bésame el trasero that's how u say you are crazy about me
loco
You can say "Estoy loco(a)".
You say, "tortuga loca."
¿Eres loco?
Me vuelves loco/a.
No estoy loco
Estamos locos
no demente, desquisiado, son others ways to say crazy.
You could say "Sombrero loco".
loco por ella