 As her family could not afford the tuition fees, she started to teach, first at St Margaret's School and then at St Andrew's School.In August 1941, she married Choy Khun Heng, employed by the Borneo Company.During the Japanese invasion of Malaya, Choy served as a second lieutenant in the women's auxiliary arm of the Singapore Volunteer Corps, where she acquired the nickname "Gunner Choy".