Tan Kah Kee
Upon returning to Singapore, Lee worked as a teacher at Tao Nan School and as a translator at a Chinese-language newspaper company. He also worked as an assistant field surveyor with the Public Works Department. In 1915, he joined the China Guohua Company owned by Tan Kah Kee, and became Tan's protégé. He was promoted to the manager of the Tan Kah Kee Rubber Company in 1917. Three years later, he married Tan's daughter, Tan Ai Leh ().