Household Questionnaire: 6.5 million copies, each copy consisting of 2 sheets of A3 paper, both sides printing and folded and stapled together in the middle with two-hole punched for bundling.

• 家庭问卷:650万份，每份由2张A3纸张组成，双面印刷，中间对折装订，并中间打两孔以便打包捆扎