Open your booklets, pick up your pencils and put on your pollution masks -- it's test time for one smog-covered school in China.
원문출처 : http://www.cnn.com/2016/12/21/asia/china-smog-student-test/index.html
원문출처 : http://www.cnn.com/2016/12/21/asia/china-smog-student-test/index.html