Chinese Premier Wen Jiabao (3rd L, front) extends festive greetings to Chinese oil workers who are on duty during the Spring Festival via videoconferencing at a command center of the Changqing Oilfield in Qingyang, northwest China's Gansu Province, Jan. 21, 2012. Wen Jiabao visited the Longdong area of Changqing oilfield Saturday. [Photo/Xinhua]