On July 22 , 1940 , a campaign preparation order to attack the Zhengtai Railway , jointly signed by Zhu De , Peng Dehuai , and Zuo Quan , was sent to Yan'an and all units of the Eighth Route Army . 
What was the , purpose and goal of this campaign ? ? ? ? 
It was to break through the Japanese army 's siege policy against base areas behind enemy lines , and to avert the crisis of China 's compromise and surrender . 
It was to overcome this crisis . 
Well , the Hundred Regiments Offensive was divided into three phases . 
Beginning from August 20 , from August 20 to September 10 , the main purpose of the ... . 
