Thank you is the author's gratitude to all the teachers, classmates, parents and friends who helped him in the process of writing the paper. Whether you write a thank-you note seriously or not can also directly tell whether you are a grateful person. Just as others help us when we need it, we will say' thank you' when we open our mouths. In a school and scientific research department, when you finish your thesis for two years, three years or even longer, you not only learn some knowledge, but also learn some professional skills and techniques, and even the process and methods of thinking, creating and working, which may be your future livelihood. Can you not thank those who have funded you, helped you and supported you?