A citizen walks in the fog-shrouded Liuzhou City, southwest China's Guangxi Zhuang Autonomous Region, Nov. 25, 2012. (Xinhua/Li Hanchi)

Citizens walk in the fog-shrouded Liuzhou City, southwest China's Guangxi Zhuang Autonomous Region, Nov. 25, 2012. (Xinhua/Li Hanchi)

A citizen walks in the fog-shrouded Liuzhou City, southwest China's Guangxi Zhuang Autonomous Region, Nov. 25, 2012. (Xinhua/Li Hanchi)

Citizens walk in the fog-shrouded Liuzhou City, southwest China's Guangxi Zhuang Autonomous Region, Nov. 25, 2012. (Xinhua/Li Hanchi)

A citizen rides a bike in the fog-shrouded Liuzhou City, southwest China's Guangxi Zhuang Autonomous Region, Nov. 25, 2012. (Xinhua/Li Hanchi)