sentence: Several bicycle racers dressed in motocross suits and wearing helmets are lined up at the start line, waiting to race. sentence:  The race begins, and all bikers race down a hill, toward a jump. sentence:  The bikers jump off a hill, but one of the bikers, dressed in red and black, tumbles to the ground. sentence:  The biker immediately behind him, dressed in red, white and blue, tries to avoid the fallen biker, and falls to the ground as well. sentence:  The other bikers race off. sentence:  The biker in black and red immediately trots off the track, while the biker in red, white and blue, is clearly injured and struggles to get to his knees. sentence:  Three men dressed in black jackets come to the aid of the first biker.