Carrying his medical bag, Zeng Zhongwen walks to the construction site of the Qinghai-Tibet electricity network project at Golmud, Northwest China’s Qinghai province, on Sept 12, 2011. [Photo/Xinhua]

Zeng Zhongwen calls his wife on the Mid-Autumn Festival on Sept 12, 2011 at Golmud, Northwest China’s Qinghai province, on Sept 12, 2011. [Photo/Xinhua]