Postgraduate volunteers who are to set out on their obligation as assisting tutors to Inner Mongolia pose for photos during the setting-off ceremony in Guiyang, southwest China's Guizhou Province, August 25, 2009. [Xinhua]

Postgraduate volunteers who are to set out on their obligation as assisting tutors wave their banners during the setting-off ceremony in Guiyang, southwest China's Guizhou Province, August 25, 2009. [Xinhua]