"zhuāntí" is a noun in Chinese, which refers to the activities or contents of in-depth research, discussion or reporting on a specific theme, problem or field. Topics can involve various fields, such as academic research, news reports, policy analysis, etc.

The special topic is characterized by in-depth analysis and discussion around a specific theme. Compared with general topics, special topics are usually more in-depth and targeted, which can help people better understand a problem or phenomenon.

For example, a theme about environmental protection may include the following aspects:

1. Causes and effects of environmental pollution;

2. Environmental protection policies and regulations;

3. Practice and technology of sustainable development;

4. Public participation and environmental education.

Through such a special topic, people will have a deeper understanding of the importance, challenges and solutions of environmental protection.

In academic research, topics are usually presented in the form of papers, reports or seminars. In news reports, special reports usually include a series of in-depth reports, interviews and commentary articles to show many aspects of a theme. In policy analysis, special topics usually involve in-depth research and discussion of specific policies or issues, providing reference for decision makers.