Core Viewpoint - The article discusses the extensive research conducted by Professor Jin Shan from Hainan University on the Japanese occupation of Hainan Island during World War II, highlighting the importance of historical documentation and field investigations in understanding this period [6][10]. Group 1: Research Background - Jin Shan has been researching the Japanese occupation of Hainan since 2006, discovering a significant lack of local resources but finding ample documentation in Japan due to extensive studies conducted during the occupation [6][7]. - His research has led to the accumulation of over 30 million words of textual materials, photographs, and labor lists, which he meticulously organizes and translates [7][8]. Group 2: Methodology - Jin emphasizes the necessity of combining historical documents with field investigations to validate findings, citing examples of Japanese authors who conducted on-site research during the occupation [8]. - He undertook a three-year effort to translate a significant historical document, demonstrating the importance of thorough fieldwork to ensure accurate translations [8]. Group 3: Ongoing Efforts - Jin continues to travel to Japan annually to gather new materials, often spending extended periods in libraries and archives to maximize his research output [6][9]. - He expresses urgency in his work, noting the loss of potential informants over time, which drives his commitment to document and preserve this historical knowledge [9]. Group 4: Purpose of Research - The research aims not only to collect evidence of Japanese war crimes but also to provide future generations with a comprehensive understanding of Hainan's social conditions during the war [10].