2. During the Spring and Autumn Period, the State of Jin and the State of Chu fought in Chengpu (southwest of Juancheng, Shandong Province), kept their previous promises, and withdrew for 90 miles (see the twenty-eighth year of Xi Gong in Zuo Zhuan); Shed: In ancient times, marching thirty miles was a shed. Later it was used to describe giving in to others instead of fighting.