Hu Zhisheng and his student Sun Xiaofeng are seen in Math lesson at Yantai primary school in Yantai Village of Lianhua Township in Tieling City, northeast China's Liaoning Province, Jan. 7, 2019. Located in a remoted mountain village, most students of Yantai school had transferred to other places outside the mountain. Sun Xiaofeng, a third grade student, became the only student of the school in September last year taught by Hu Zhisheng, the only one faculty of Yantai primary school. (Xinhua/Yao Jianfeng)