The free version is suitable for duplicate checking of the first draft, and it can be checked twice a day for free, but its database is relatively small, and the duplicate checking result may not be accurate enough.
Professional edition and extreme edition are suitable for duplicate checking of Chinese manuscripts and final drafts. The database of Extreme Edition is more comprehensive, and the duplicate checking results are more accurate, but the price is also higher. English version is suitable for duplicate checking of English papers.
Therefore, for students who need to check the duplicate, it is more cost-effective to use the free version of PaperYY to check the duplicate draft. However, if you need more accurate duplicate checking results, you can choose professional edition or extreme edition. It should be noted that it is best to use a test system consistent with the school to check the final draft to ensure that the repetition rate of the paper meets the requirements of the school.