Three men in green outfits watch as a fourth man breakdances in front of a crowd and a tour bus parked on the street.
Three men in green outfits set down mats to start breakdancing while a forth man sits by and waits his turn to perform for the crowd.
The three men who watch can not also set down mats.  The fourth man who sits by and waits, can not be the fourth man who breakdances.
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