The sentence in the question comes from the text "Don't forget to dig people when drafting".
The work "People Digging Wells after Towing Water" tells the story of a small village called Shazhouba outside Ruijin. Chairman Mao lived in Jiangxi when he led the revolution. Shazhouba is a water-deficient village, and there is no well in the village. It is difficult for people living here to drink water, so they have to go to the river a few kilometers away to pick it. Chairman Mao decided to lead the Red Army soldiers to dig a well for the villagers. One day, Chairman Mao led several Red Army soldiers to the village to investigate the water source, chose a place with wet grass and began to dig.