You must first know the geographical choice of learning by yourself, and you have a certain knowledge reserve in this respect. Secondly, I should be interested in this topic field. Finally, choose some small, meaningful and novel ones.

The train of thought of this research field: raising questions, including defining the concept of questions and explaining the importance or significance of research. Analyze the problem, summarize the current situation, advantages and disadvantages of the research object or problem, point out what problems exist, and analyze their causes and harmfulness. Solve the problems, put forward the arguments of this paper and the ways, countermeasures and suggestions to solve these problems.