First, the purpose of proof is clear: the purpose of changing the lawyer's license is to prove that the lawyer has successfully obtained a new lawyer's practice certificate and cancelled the old lawyer's practice certificate.

2. Cancellation of lawyer's practice certificate: A lawyer needs to clearly indicate in the certificate that the original lawyer's practice certificate has been cancelled. Provide a copy of the old lawyer's practice certificate and cancellation certificate. The cancellation certificate can be a certificate issued by the local judicial administrative department or the bar association.

Iii. Proof of obtaining a new lawyer's practice certificate: A lawyer needs to provide a copy of the new lawyer's practice certificate for renewal, and indicate the issuing time and validity period of the certificate.

Four. Proof of lawyer's personal information: the lawyer's personal information, such as lawyer's name, practice certificate number, etc., needs to be included in the renewal of the lawyer's certificate.

To sum up, the lawyer's replacement should include the cancellation certificate of the old certificate, the copy of the new certificate and the lawyer's personal information certificate to prove that the lawyer's replacement is successful. It is suggested that lawyers should provide detailed materials when preparing the certificate, and affix the official seal of the law firm on the certificate to increase the authority and reliability of the certificate.