Ku's grandfather relied on his talented son as an interpreter. Although his grandfather dealt very successfully with the Japanese, he actually harbored a deep antipathy for them. While the children of other elite families went off to study in Japan, Ku's father was sent to a private school in Taiwan, where he was steeped in the Chinese classics and became an expert calligrapher.
然而祖父其實十分厭恨日本人，因而不願意像當時的台灣仕紳一樣，讓兒子赴日留學，反倒送兒子進入私塾，飽讀漢文經書，還練得一手好毛筆字。