Cai Yong
Sometime in the 180s, when Cai Yong was living in Wu Commandery, Gu Yong met him and learnt calligraphy and music from him. While studying under Cai Yong's tutelage, Gu Yong showed that he was not only diligent and focused in his studies, but also fast-learning and easily teachable. As a result, he earned high praise from Cai Yong, who told him: "You will definitely reach the pinnacle of success. I offer you a new name – the same as mine." Gu Yong thus changed his given name to "Yong" () which was similar to Cai Yong's "Yong" (). He also adopted "Yuantan" (), which literally means "top praise", as his courtesy name to reflect the high praise he received from his mentor.