When writing a paper, the first author is the manuscript writer of the paper. The person signed by the second author is generally the person who checks and proofreads and puts forward suggestions for minor repairs and changes, and sometimes the person who needs to sign for some benefit. For example, I wrote a paper and won the second prize at the municipal level. The first signature is myself, and the second signature is my former teacher's son. Because his son's promotion title lacks the conditions of municipal papers, I asked to hang his son's name, and I can only agree. You got it? Good luck!