Legal analysis: I need to sign. The power of attorney shall include the following contents: 1. Customer's personal information. Name, contact information, ID number, address, etc. ; 2. Relevant information of the trustee. Name, contact information and address, etc. If the trustee is a lawyer, just write the name of the lawyer and the name of the law firm; 3. Reasons for entrustment and agency authority. If there is special authorization, the specific scope of authorization shall be stated; 4. Signature of the client and the trustee, indicating the year, month and day.

Legal basis: Article 3 of the Lawyers Law of People's Republic of China (PRC), lawyers must abide by the Constitution and laws, and strictly abide by lawyers' professional ethics and practice discipline.

Lawyers' practice must be based on facts and take the law as the criterion.

Lawyers' practice should be supervised by the state, society and the parties concerned.

Lawyers' legal practice is protected by law, and no organization or individual may infringe upon the legitimate rights and interests of lawyers.