"The enemy advances and I retreat; The enemy is stationed, and I am disturbing; The enemy is tired and I fight; The enemy retreated and chased me. " The 16-character formula of "the enemy advances and I retreat"; The enemy is stationed, and I am disturbing; The enemy is tired and I fight; "The enemy retreats and we chase" is the basic guiding principle of guerrilla warfare of the Red Army. The core of this principle is active defense, advancing by retreating, attacking by defending, preserving oneself and destroying the enemy.