The postal code of Dongying District is 257000 (Kenli, Hekou, Guangrao and Lijin are different from this postal code, for example, Kenli is 257500). As long as it is sent to Dongying, you can definitely write this postal code, because as long as it is sent to Dongying, it will be delivered to you according to the address, but specifically, the postal codes in different areas of Dongying are actually different. For example, Xisi Road Oilfield Machinery Factory is 257067. Jinan Road Teachers College 257097, Petroleum University 25706 1, Shengli Hospital 257055. Unless you know the exact postal code of that lot, write 257000.