Philip, a British professor, once classified the performance of "original contribution" of doctoral thesis into the following 15 types:

1. Record the main part of information in words for the first time;

2. Continue the work that has been determined originally;

3. Carry out the original design work of the tutor;

4 provide a single original technology or observation, or obtain original results in non-original but sufficient research work;

5. There are many original ideas, methods and explanations actually carried out by other graduate students;

6. Show originality when testing other people's ideas;

7. Carry out experimental work that no one has done before;

8. Synthesize a compound that has not been manufactured before;

9. Use known materials to get new explanations;

10. Do some research work in your country that has only been done in other countries;

1 1. Apply a special technology to a new research field;

12. Provide new evidence for an old problem;

13. Carry out interdisciplinary work and adopt different methods;

14. pay attention to the new research fields that have not yet started in this discipline;

15. Enhance human knowledge in an unprecedented way.