A man goes to a pet shop to buy a parrot. "We have three." says shopkeeper. 
"This blue one speaks four languages and it costs $1000 and the red one knows
six languages and it costs $ 2000. The orange one over there costs $3000 but
doesn't talk at all."

"Three thousand !" exclaims the man. "How come it's more expenxive??"

"Well, we don't know what he does, but the other two parrots call him'Boss'."