Teacher Cheng-En Li believes that the two individuals who have had the greatest influence on him are Dr. Yao-Song Lin and Dr. Yi-Ru Yang. During his time in college and graduate school, he conducted research on frog-related topics in Dr. Lin's laboratory. Dr. Lin always spared no effort in promoting conservation concepts, never easily giving up even in the face of difficulties, and tirelessly working to persuade those with differing opinions. Dr. Lin's decades of passion for conservation work greatly inspired him.

During high school, he became acquainted with Dr. Yi-Ru Yang, a pioneer in frog conservation in Taiwan. He worked with Dr. Yang on numerous frog surveys and promotional activities, as well as organizing conservation volunteers, leading to the establishment of the Taiwan Amphibian Conservation Association. He observed that grassroots conservation volunteer groups evolved from a gathering of amphibian enthusiasts into citizen scientists and it profoundly influenced science education and ecological conservation in Taiwan. This process has been a great source of inspiration for Teacher Li.