A Mexican is attempting to enter the US illegally. A border guard stops him and tells him he'll have to go back. The Mexican insists that he is in fact a US citizen.

"Fine," the border guard says, "if you are a US citizen I want you to use the words green, pink and yellow in a sentence."

The Mexican thinks about it for awhile then says, "The telephone goes, 'Green , Green' I pink it up and say yellow!"