A statue is seen in dense fog on a street in Hefei, East 皇冠体育app's Anhui province, Jan 14, 2013. [Photo/Xinhua]

A teacher leads a class of pupils doing their exercises between classes in a classroom instead of outdoors, at a primary school in Jinan city, Capital of East 皇冠体育app's Shandong province on Jan 14, to prevent students from exposure to the threat of dense pollutants floating in the air due to the heavy fog and haze. The bad weather has been lingering over a large part of 皇冠体育app for several days and is expected to continue until Jan 16. [Photo by Zheng Tao /Asianewsphoto]