Jiang Guonan composes a blackboard bulletin at Jigao Primary School in Xiongcun Township, Lichuan County, east China's Jiangxi Province, Dec. 3, 2020. Jiang Guonan has taught at Jigao Primary School in his hometown since he graduated from high school in 1978. In the 42 years to come, the teacher remained on this rural post, though more and more his colleagues chose to leave for teaching at schools in towns amid urbanization development. By September 2019, Jiang has become the only teacher at Jigao Primary School. He applied to stay for the seven-year-old first-grader Jiang Haotian who is a left-behind child living with his grandparents. (Xinhua/Hu Chenhuan)

Jiang Guonan (L) and his student Jiang Haotian go downstairs after class at Jigao Primary School in Xiongcun Township, Lichuan County, east China's Jiangxi Province, Dec. 3, 2020. Jiang Guonan has taught at Jigao Primary School in his hometown since he graduated from high school in 1978. In the 42 years to come, the teacher remained on this rural post, though more and more his colleagues chose to leave for teaching at schools in towns amid urbanization development. By September 2019, Jiang has become the only teacher at Jigao Primary School. He applied to stay for the seven-year-old first-grader Jiang Haotian who is a left-behind child living with his grandparents. (Xinhua/Hu Chenhuan)

Jiang Guonan (front) and his student Jiang Haotian play with a basketball at Jigao Primary School in Xiongcun Township, Lichuan County, east China's Jiangxi Province, Dec. 3, 2020. Jiang Guonan has taught at Jigao Primary School in his hometown since he graduated from high school in 1978. In the 42 years to come, the teacher remained on this rural post, though more and more his colleagues chose to leave for teaching at schools in towns amid urbanization development. By September 2019, Jiang has become the only teacher at Jigao Primary School. He applied to stay for the seven-year-old first-grader Jiang Haotian who is a left-behind child living with his grandparents. (Xinhua/Hu Chenhuan)

Jiang Guonan (R) teaches his student Jiang Haotian in a handicraft class lesson at Jigao Primary School in Xiongcun Township, Lichuan County, east China's Jiangxi Province, Dec. 3, 2020. Jiang Guonan has taught at Jigao Primary School in his hometown since he graduated from high school in 1978. In the 42 years to come, the teacher remained on this rural post, though more and more his colleagues chose to leave for teaching at schools in towns amid urbanization development. By September 2019, Jiang has become the only teacher at Jigao Primary School. He applied to stay for the seven-year-old first-grader Jiang Haotian who is a left-behind child living with his grandparents. (Xinhua/Hu Chenhuan)

Jiang Guonan (R) and his student Jiang Haotian clean the kitchen at Jigao Primary School in Xiongcun Township, Lichuan County, east China's Jiangxi Province, Dec. 3, 2020. Jiang Guonan has taught at Jigao Primary School in his hometown since he graduated from high school in 1978. In the 42 years to come, the teacher remained on this rural post, though more and more his colleagues chose to leave for teaching at schools in towns amid urbanization development. By September 2019, Jiang has become the only teacher at Jigao Primary School. He applied to stay for the seven-year-old first-grader Jiang Haotian who is a left-behind child living with his grandparents. (Xinhua/Hu Chenhuan)

Aerial photo shows Jiang Guonan and his student Jiang Haotian playing badminton at Jigao Primary School in Xiongcun Township, Lichuan County, east China's Jiangxi Province, Dec. 3, 2020. Jiang Guonan has taught at Jigao Primary School in his hometown since he graduated from high school in 1978. In the 42 years to come, the teacher remained on this rural post, though more and more his colleagues chose to leave for teaching at schools in towns amid urbanization development. By September 2019, Jiang has become the only teacher at Jigao Primary School. He applied to stay for the seven-year-old first-grader Jiang Haotian who is a left-behind child living with his grandparents. (Xinhua/Hu Chenhuan)

Jiang Guonan (L) and his student Jiang Haotian take an after-lunch walk at Jigao Primary School in Xiongcun Township, Lichuan County, east China's Jiangxi Province, Dec. 3, 2020. Jiang Guonan has taught at Jigao Primary School in his hometown since he graduated from high school in 1978. In the 42 years to come, the teacher remained on this rural post, though more and more his colleagues chose to leave for teaching at schools in towns amid urbanization development. By September 2019, Jiang has become the only teacher at Jigao Primary School. He applied to stay for the seven-year-old first-grader Jiang Haotian who is a left-behind child living with his grandparents. (Xinhua/Hu Chenhuan)

Jiang Guonan shows group photos of him and students of the previous classes at home in Lichuan County, east China's Jiangxi Province, Dec. 4, 2020. Jiang Guonan has taught at Jigao Primary School in his hometown since he graduated from high school in 1978. In the 42 years to come, the teacher remained on this rural post, though more and more his colleagues chose to leave for teaching at schools in towns amid urbanization development. By September 2019, Jiang has become the only teacher at Jigao Primary School. He applied to stay for the seven-year-old first-grader Jiang Haotian who is a left-behind child living with his grandparents. (Xinhua/Hu Chenhuan)

Jiang Guonan (L) teaches his student Jiang Haotian in a math lesson at Jigao Primary School in Xiongcun Township, Lichuan County, east China's Jiangxi Province, Dec. 3, 2020. Jiang Guonan has taught at Jigao Primary School in his hometown since he graduated from high school in 1978. In the 42 years to come, the teacher remained on this rural post, though more and more his colleagues chose to leave for teaching at schools in towns amid urbanization development. By September 2019, Jiang has become the only teacher at Jigao Primary School. He applied to stay for the seven-year-old first-grader Jiang Haotian who is a left-behind child living with his grandparents. (Xinhua/Hu Chenhuan)

Jiang Guonan (L) and his student Jiang Haotian play a game at Jigao Primary School in Xiongcun Township, Lichuan County, east China's Jiangxi Province, Dec. 3, 2020. Jiang Guonan has taught at Jigao Primary School in his hometown since he graduated from high school in 1978. In the 42 years to come, the teacher remained on this rural post, though more and more his colleagues chose to leave for teaching at schools in towns amid urbanization development. By September 2019, Jiang has become the only teacher at Jigao Primary School. He applied to stay for the seven-year-old first-grader Jiang Haotian who is a left-behind child living with his grandparents. (Xinhua/Hu Chenhuan)

Jiang Guonan (L) and his student Jiang Haotian do physical exercise at Jigao Primary School in Xiongcun Township, Lichuan County, east China's Jiangxi Province, Dec. 3, 2020. Jiang Guonan has taught at Jigao Primary School in his hometown since he graduated from high school in 1978. In the 42 years to come, the teacher remained on this rural post, though more and more his colleagues chose to leave for teaching at schools in towns amid urbanization development. By September 2019, Jiang has become the only teacher at Jigao Primary School. He applied to stay for the seven-year-old first-grader Jiang Haotian who is a left-behind child living with his grandparents. (Xinhua/Hu Chenhuan)

Jiang Guonan (L) and his student Jiang Haotian take an after-lunch walk at Jigao Primary School in Xiongcun Township, Lichuan County, east China's Jiangxi Province, Dec. 3, 2020. Jiang Guonan has taught at Jigao Primary School in his hometown since he graduated from high school in 1978. In the 42 years to come, the teacher remained on this rural post, though more and more his colleagues chose to leave for teaching at schools in towns amid urbanization development. By September 2019, Jiang has become the only teacher at Jigao Primary School. He applied to stay for the seven-year-old first-grader Jiang Haotian who is a left-behind child living with his grandparents. (Xinhua/Hu Chenhuan)

Jiang Guonan offers study guidance to his student Jiang Haotian at Jigao Primary School in Xiongcun Township, Lichuan County, east China's Jiangxi Province, Dec. 3, 2020. Jiang Guonan has taught at Jigao Primary School in his hometown since he graduated from high school in 1978. In the 42 years to come, the teacher remained on this rural post, though more and more his colleagues chose to leave for teaching at schools in towns amid urbanization development. By September 2019, Jiang has become the only teacher at Jigao Primary School. He applied to stay for the seven-year-old first-grader Jiang Haotian who is a left-behind child living with his grandparents. (Xinhua/Hu Chenhuan)

Jiang Guonan (L) talks about a wild fruit with his student Jiang Haotian during an after-lunch walk at Jigao Primary School in Xiongcun Township, Lichuan County, east China's Jiangxi Province, Dec. 3, 2020. Jiang Guonan has taught at Jigao Primary School in his hometown since he graduated from high school in 1978. In the 42 years to come, the teacher remained on this rural post, though more and more his colleagues chose to leave for teaching at schools in towns amid urbanization development. By September 2019, Jiang has become the only teacher at Jigao Primary School. He applied to stay for the seven-year-old first-grader Jiang Haotian who is a left-behind child living with his grandparents. (Xinhua/Hu Chenhuan)

Jiang Haotian reads a book at the reading room of Jigao Primary School in Xiongcun Township, Lichuan County, east China's Jiangxi Province, Dec. 3, 2020. Jiang Guonan has taught at Jigao Primary School in his hometown since he graduated from high school in 1978. In the 42 years to come, the teacher remained on this rural post, though more and more his colleagues chose to leave for teaching at schools in towns amid urbanization development. By September 2019, Jiang has become the only teacher at Jigao Primary School. He applied to stay for the seven-year-old first-grader Jiang Haotian who is a left-behind child living with his grandparents. (Xinhua/Hu Chenhuan)

Jiang Guonan (R) and his student Jiang Haotian have a meal at Jigao Primary School in Xiongcun Township, Lichuan County, east China's Jiangxi Province, Dec. 3, 2020. Jiang Guonan has taught at Jigao Primary School in his hometown since he graduated from high school in 1978. In the 42 years to come, the teacher remained on this rural post, though more and more his colleagues chose to leave for teaching at schools in towns amid urbanization development. By September 2019, Jiang has become the only teacher at Jigao Primary School. He applied to stay for the seven-year-old first-grader Jiang Haotian who is a left-behind child living with his grandparents. (Xinhua/Hu Chenhuan)

Jiang Guonan teaches his student Jiang Haotian in a math lesson at Jigao Primary School in Xiongcun Township, Lichuan County, east China's Jiangxi Province, Dec. 3, 2020. Jiang Guonan has taught at Jigao Primary School in his hometown since he graduated from high school in 1978. In the 42 years to come, the teacher remained on this rural post, though more and more his colleagues chose to leave for teaching at schools in towns amid urbanization development. By September 2019, Jiang has become the only teacher at Jigao Primary School. He applied to stay for the seven-year-old first-grader Jiang Haotian who is a left-behind child living with his grandparents. (Xinhua/Hu Chenhuan)