If the school requires a duplicate check on the first draft, and it has passed the duplicate check, then a second duplicate check is usually not needed. However, if the school has doubts about the results of duplicate checking, or thinks it is necessary to carry out duplicate checking, then it is necessary to carry out duplicate checking according to the requirements of the school.

If the contents of the first draft have changed greatly after modification and polishing, it may need to be checked again to ensure that the modified contents are not repeated. Whether it is necessary to check again depends on the specific situation and the requirements of the school. If you have any questions about the results of the duplicate inspection, or need further modification and polishing, you may need to check the duplicate again.