1. First, first-hand information. First-hand materials include written materials and digital materials (including charts) directly related to the topic, such as statistics, typical cases, experience summary, etc. , including perceptual materials obtained from personal practice. This is the basic basis for the thesis to put forward arguments and propositions. Without these materials, the graduation thesis written can only become empty talk and has no practical value. In order to obtain first-hand information,

2. Second, other people's research results. This refers to the latest progress in academic research on this subject at home and abroad. Writing a graduation thesis is not done out of thin air, but on the basis of other people's research results. Therefore, people can take this as a starting point and get useful inspiration, reference and guidance. You can learn from others for problems that others have not solved or are not satisfied with.

3. Third, materials of marginal disciplines. Today is the information age.