Originated from the biography of Han Yang Chang, and also found in the biography of the Empress Fu in the later Han Dynasty. During the reign of Emperor Xiandi in the Eastern Han Dynasty, the royal family was very declining, and the military and political power had fallen into the hands of Cao Cao. In order to realize his ambition of being king, Cao Cao cultivated his own private forces extensively, and even some guards in the palace became his cronies. Zhao Yan was a counselor under Emperor Xian of Han Dynasty, and he often gave advice to Emperor Xian of Han Dynasty. Cao Cao hated him very much, so he designed and killed Zhao Yan, and even some people close to Zhao Yan were killed by him. Later, Cao Cao went to see Emperor Xian of Han Dynasty because of something. Emperor Xian of Han Dynasty said angrily, "It would be very good if you could help me. Otherwise, I hope you will be kind enough to leave me alone. " Cao Cao was shocked and kowtowed to ask him to go out. Emperor Xian of Han ordered the warriors to carry him out with a knife. He thought that Emperor Xian of Han was going to kill him. When he came out from under the lance, he was so scared that he was sweating like a pig. After that, he dared not come to court again for a long time. Later, people used "sweating like a pig" to describe extreme fear or extreme shame. It is now used to describe sweating a lot.