The South of the Mountain Is "Mulberry"

One sunny afternoon, Zhongbai heard the boss's high-pitched and harsh voice: "The south of the water is yin, why is the south of the mountain?" Xia Baiyi! !" The whole class gasped, and only Xia Baiyi dared to sleep in the boss class~~ He stood up calmly, and when he was about to speak, he caught a glimpse of the trembling shoulders of the little man in the front row, and the corners of his mouth slightly curved, and he suddenly changed his mind. "The south of the mountain is mulberry..." After a moment, he saw the little man's straight back, and added "Mo Sang's mulberry"...