What is the relationship between Anqing and Tongcheng?

Inclusion relation. According to Baidu Encyclopedia, Tongcheng is a county-level city in Anqing, Anhui Province, China. Both are inclusive. Tongcheng, a county-level city under the jurisdiction of Anhui Province and managed by Anqing City, is located in the southwest of central Anhui Province, with Dabie Mountain in the west and Yangtze River in the east.