Dancers perform before track and field events at the National Stadium, also known as the Bird's Nest, during Beijing 2008 Olympic Games in Beijing, China, Aug. 21, 2008. (Xinhua/Guo Dayue)

Dancers perform before track and field events at the National Stadium, also known as the Bird's Nest, during Beijing 2008 Olympic Games in Beijing, China, Aug. 21, 2008. (Xinhua/Guo Dayue)

Dancers wave to the spectators before track and field events at the National Stadium, also known as the Bird's Nest, during Beijing 2008 Olympic Games in Beijing, China, Aug. 21, 2008. (Xinhua/Guo Dayue)