Can the ancient Ryukyu people speak Chinese?

Like other countries in East Asia, Chinese characters are the official characters of Ryukyu. Chinese is used in diplomatic exchanges with China, North Korea and Viet Nam. The inscriptions of Ryukyu people and the genealogy of the gentry are also recorded in Chinese. Communication with Ming and Qing Dynasties and Japan is often very important. During the Ming and Qing Dynasties, Ryukyu sent overseas students to imperial academy in Nanjing and Beijing and Ryukyu Pavilion in Fuzhou to learn the language of China. According to the research on the preserved textbooks of Mandarin used by Ryukyu people, the Mandarin learned by Ryukyu people is influenced by Fujian dialect, especially Fuzhou dialect, which is strictly called "Fuzhou Mandarin". In the early days, Ryukyu used Chinese in diplomatic occasions and official documents. In addition to Chinese characters, Ryukyu has its own characters, the so-called "ball character".