One summer night, when he was reading outside, he suddenly saw fireflies flying in the air like stars in Garden Metallurgy. He thought that the glow of fireflies was not just like a lamp in the dark. So I can study hard all night! Thinking of this, he immediately found a white silk and plunged it into a small pocket, and caught dozens of fireflies and put them in. It really worked.
It was through this weak light and persistent study that Che Yin's knowledge improved day by day and eventually became an official in North Korea.