Sun Kang was born in a poor family in Jin Dynasty. He used snow lanterns to read at night. From Liao Yongxian's Business Friends Record, Volume 4: "Sun Kang, a native of Jin Jingzhao, is sensitive and eager to learn, and his family is poor and has no oil. He has tasted the snow in winter. " The latter describes studying hard in a difficult environment.

Sun Kang's allusion to snow:

Sun Kang, a native of Jin Dynasty, liked reading since childhood, but his family was poor. In order to make a living, his family had to work during the day. Although Sun Kang is very young, he is no exception. There is no time during the day, and there is no light at home at night, so I can't read.

When I was a child, Sun Kang asked his father, "Why do people have oil lamps at home and we don't?" Father replied, "Oil lamps are very expensive. If we want to buy it, the whole family will starve. " Sun Kang Jr. was so wise that he never mentioned it again.

All the books I read are borrowed, and I am very trustworthy. Be sure to return it when the time comes. I often worry because I have no time to read. He tried to read in the moonlight, but it was too dark and his eyes were tired.

One winter, it snowed heavily and the moonlight was bright. He suddenly found that the words on the book could be seen clearly in the snow. Sun Kang was very happy. He is busy reading in the snow. When he is tired, he lies in the snow and reads by the reflection of the snow.

Since then, every time it snowed, Sun Kang ignored the cold and read in the snow. After a long time, his hands and feet were covered with frostbite, but he still read a lot of books in this way. Finally, the official paid homage to the ancient doctor. When they learned the story, many people were moved to tears.

Capsule fireflies reflect snow:

Sun Kang's story of "reflecting snow" and Che Yin's story of "saccharum glomeratum" constitute the idiom "saccharum glomeratum reflecting snow".

Che Yin was born in Nanping County, Eastern Jin Dynasty. His grandfather Che Jun served as the magistrate of Soochow during the Three Kingdoms period.

Because of the famine, he asked for relief to the people and was executed by Sun Hao, the fatuous Lord of Wu. From then on, Che Yin's family was penniless. Che Yin was smart and studious since childhood, determined to study hard and dabbled in all kinds of knowledge. Taishou Wang once said to his father Che Yu, "This son should be a great scholar and can go to a junior college." .

Because the family is poor, there is no money to light a lamp when reading at night. One summer night, he sat in the yard and meditated, and saw many fireflies flying in the air, like many small lights flashing in the night sky. His heart can't help but light up. He immediately caught some fireflies and put them in a pocket made of silk, and the fluorescence came out.

Che Yin studied hard day and night by the faint light of fireflies.

Under the guidance of his father, Che Yin finally became a very learned man. He has served as assistant minister of Zhongshu, assistant middle school, imperial academy erudite, a title of generals in ancient times, Taichang, general of protecting the army, Danyang Yin, and official minister. Yuan Xian, the son of Wang Sima Daozi of Huiji, spoke out bravely, forced him to commit suicide, and pursued Zhongjun after his death.