The lingering sound echoes around the beams and shakes the woods. Yangguan. Three layers of complex strings. The sharp and melodious music echoes around the beams for three days. Pearls fall on the jade trays. The oriole comes out of the valley and sings three times. It sighs. The five-note sound is not complete. The sounds of the mountains and flowing water are as if they are far away from nothingness. The sonorous, powerful and heart-wrenching sounds are endless. It's like a wisp of sound, holding back the clouds, high mountains and flowing water, the white snow in spring, the rhythmic and deafening sound of nature