May refer to: "May 7th Workers" refers to those who worked in petroleum, coal, chemical industry, construction, building materials, transportation, metallurgy, nonferrous metals, medicine, textile, machinery, light industry, agriculture, forestry, water conservancy, animal husbandry, electric power, military industry and other 19 state-owned enterprises in the 1960s and 1970s, and engaged in self-help or enterprise-assisted work.