Du Yin, a teacher of Hunan "Micro Power" Art Training School, is a national-level Putonghua proficiency tester, an examiner for the joint examination of broadcasting and hosting major in Hunan Province, a member of the evaluation expert group of Hunan language and writing work, and the vice president of Hunan Logic Society. Over the years, he has taught broadcasting and vocalization, speech and debate, impromptu comments and other courses in colleges and universities. He was invited to teach at Kamei University in Korea for three years and was awarded the Meritorious Medal by Korea International Exchange Association. He has published more than 20 academic papers at home and abroad, edited two excellent course textbooks in colleges and universities, and was awarded the title of "excellent tester" by the State Language Committee. I recommend you to know about it and hope it will help you.