Open the Word document.

Click the View option in the toolbar.

Click "Compare" in "Spelling and Grammar".

Select the "original" and "revised" versions of the paper for comparison.

When you click OK, Word will list the differences between the two documents.

In addition, some online duplicate checking tools can also be used to check duplicate papers, such as paperfree, papertime, paperday and so on. These tools can detect whether there are similar or duplicate parts in the text with other documents in the network or database. Usually, you need to purchase or register an account to use these tools. In the process of use, you need to upload the test paper to the website and wait for a period of time. The system will give a duplicate check report, which will list the parts similar to other documents and the percentage of similarity.

Please note that when checking duplicate papers, you should choose appropriate tools and platforms to ensure the credibility and accuracy of the results. At the same time, when quoting documents, we should pay attention to standardization and legality to avoid plagiarism and infringement.