You started learning in the third and fourth grades of primary school, right? In the third grade of primary school, the advance rate of mass units, the advance rate between weight units and microgram mass units are only philosophical tons and kilograms, and kilograms and kilograms are the usual methods of folklore in China. There is nothing in the teaching content that 1kg= 1kg equals two kilograms, and a meal equals 1000 kg equals 1000kg equals 2000 kg. It is a municipal unit.
1 kg = 1 kg = 2kg1t =1000kg =1000kg = 2000kg. Only tons and kilograms are studied in the third and fourth grades. Kg and Jin are folk idioms in China, not international standard units, and are not included in the teaching content.