Zhang Fuyou teaches nine students at Dajiang Primary School at Dalong town of Lipu county in the Guangxi Zhuang autonomous region.

Five-year-old Wei Qiaolin is the youngest pupil in the school. Her grandmother Lin Xiujuan, 70, comes to school to take her home. Qiaolin refuses to walk the two hours back home after a tiring school day. With tears in her eyes, she tells her grandmother that her feet and legs are too painful to walk.

"She did not speak a single word or smile all day," says Zhang. "Her grandpa was an old respected teacher here. But her grandparents' love cannot replace her parents'."

Lin stays overnight with her granddaughter in the school for the night. Zhang and Lu prepare a room for young students and their grandparents to stay over when they cannot go home because of illness and bad weather.

"Compared with the children's sufferings, my boat work is not worth mentioning at all," Zhang says. "Their parents authorized me to punish the children physically. But I cannot bear to do so."

Zhang's two children work as migrant workers in Lipu. His farmer wife lives with their son and helps to take care of their grandson in the county.

Zhang visits his wife and children once every few months. He has lived by himself for two years. He is content with his life. During his free time, he tends a small patch of mountain farmland and his countless bees, as well as plays with his cat.

"My students and their families and my neighbors often come to see me. The feeling of a community is much stronger than the urban residents living in 'concrete woods'," Zhang says.

He will retire next February. His wife Xie Yujiao, 53, says he is a good husband and father. She hopes he can have a good rest after retirement and take good care of his arthritis, hypertension and heart diseases.

But Zhang assures the students and villagers that he will continue to work as a volunteer teacher and boatman until the school has no more students.

"I simply cannot bid farewell to the children," he adds.

Huo Yan contributed to the story.

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