There are five ways to serve documents, namely, direct service, lien service, entrusted service, mail service and announcement service. The first choice is direct delivery, and everything that can be delivered directly should be delivered directly. If it cannot be delivered directly, such as the recipient refuses to sign for it, it can be delivered by lien. If the addressee does not operate or live in this area, which leads to difficulties in direct delivery, he may entrust other organs or units to serve it on his behalf, or serve it by mail at the request of the addressee. If none of the above methods can be delivered, or there are many recipients of the same service, the announcement delivery method will be adopted. "