Pan Shanji teaches at Dayandong education point in Guzhai Mulam ethnic town in Liucheng of the Guangxi Zhuang autonomous region.

Pan took corn and sweet potatoes with him to his high school in Luoya town where he was a boarder in 1977. He says his headmistress Mo Rongxuan encouraged his studies, telling him: "You are the student from the mountain. I hope you can focus all your energy on studying. Don't be distracted by other things."

The former village Party secretary convinced Pan to return to the mountains to teach after he graduated from high school.

But four years after Pan returned, the village Party secretary died, leaving his 8-year-old daughter and widow in miserable circumstances.

"I made up my mind that I must marry her (the daughter) when she grows up to take care of her. So I waited for that time and married her in 1988 when I was 28 years old, quite a late marriage age for men in the village."

His wife has been paralyzed by femoral head necrosis for 20 years. "We needed the money to take care of my sick father at that time. He died several years ago. Now my elderly mother is also ill in bed. My daughter and my son are very thoughtful. My older daughter works in Liuzhou after graduating from a vocational school. Her brother, now in junior middle school, has also decided to start working as soon as possible. I will try my best to take care of my wife. This is a promise I made to her when I married her," says Pan, beginning to get emotional.

"Let's talk about something happy." He changed the topic to his work. "When I hear the children say 'Good morning teacher' to me everyday, I forget all miseries of my life," he says, with a big smile on his face but with tears in his eyes.

Today, all of his 12 students are left-behind children. Their parents are former students of Pan's who now work in Guangdong as migrant workers.