String dogs can apply for a dog certificate, as long as they issue an immunization certificate that does not meet the standards of large dogs. To apply for a dog license with a string of dogs, you need to do immunization and rabies in a pet hospital, issue a certificate, and then take an inch of photos of the dogs. Bring your ID card and household registration book to the dog registration center to fill in the form, and you can get a dog license after completing the formalities.