Introduction to the Central Auditorium: When you walk into Yangjialing, the first thing you see is the site of the "Seventh National Congress". The landmark "Seventh National Congress" of the Central Committee of the Communist Party of China was held here from April to June 1945. The meeting lasted for 50 days and was attended by 755 representatives. The central auditorium at that time was surrounded by green pines and cypresses from the front and back. Against the blue sky, a bright red flag fluttered in the wind on the top of the auditorium. Entering the auditorium, the wooden chairs, rostrum, statue of Marx and Engels, red flag, and large slogan "Victorious March Under the Flag of Mao Zedong" are still the same. Standing in the middle of the auditorium, I seem to hear the "Seventh National Congress of the Communist Party of China" in my ears. "The footsteps of the representatives came one after another, and waves of applause were heard, and a sacred passion surged into my heart.