Heavy fog forces kids to stay in classroom for exercise

A national flag flies in the hazy, foggy sky at a primary school in Jinan city, Capital of East China's Shandong province on Jan 14, 2013. [Photo by Zheng Tao /Asianewsphoto]

Students do their exercises between classes in a classroom instead of outdoors at a primary school in Jinan city, Capital of East China'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. [Photo by Zheng Tao /Asianewsphoto]