During the Cultural Revolution, Wu Guanzhong was sent to work in the countryside, met a very kind company commander and forged a friendship with him. Later, after decentralization, Wu Guanzhong returned to Beijing. The company commander was also demobilized to a town in the south of the Yangtze River. Wu Guanzhong wrote a letter to the company commander and attached a small ink painting of his own as a souvenir. The company commander wrote back that this is' a thousand miles to send goose feathers'. Originally, Wu Guanzhong was happy to see it. But later, he saw the painting he gave to the company commander at an auction in Hong Kong. He estimated that the company commander sold it at a very low price or exchanged it for something cheap. Another day, the company commander came to visit Wu Guanzhong, brought some sheets, towels and other gifts, and wanted a painting of Wu Guanzhong. But Wu Guanzhong had no intention of giving it away, so the company commander had to take it back. Wu Guanzhong wrote in his autobiography "I am responsible for Dan Qing": "I brushed away my good company commander with a thousand miles of goose feathers! I wrote an article "Turning Stone into Gold", which tells the bitter story of ruining friendship with painting. "

-I am also a foreign aid.