Staff member Sun Zongshan (2nd L) communicates with young guides at the site where the first Communist Party of China (CPC) National Congress was held in 1921, in east China's Shanghai, Aug. 13, 2019. Eight students are selected as guide to interpret for visitors as their social practice during the summer vacation. (Xinhua/Liu Ying)

　　Tang Yiting salutes to visitors at the site where the first Communist Party of China (CPC) National Congress was held in 1921, in east China's Shanghai, Aug. 13, 2019. Eight students are selected as guide to interpret for visitors as their social practice during the summer vacation. (Xinhua/Liu Ying)

　　Sa Beilei (L) and Tang Yiting encourage each other at the site where the first Communist Party of China (CPC) National Congress was held in 1921, in east China's Shanghai, Aug. 13, 2019. Eight students are selected as guide to interpret for visitors as their social practice during the summer vacation. (Xinhua/Liu Ying)

　　Sa Beilei (C) interprets for visitors at the site where the first Communist Party of China (CPC) National Congress was held in 1921, in east China's Shanghai, Aug. 13, 2019. Eight students are selected as guide to interpret for visitors as their social practice during the summer vacation. (Xinhua/Liu Ying)