This paper deals with the historical change of gòng 共 from Archaic Chinese to ka7 共 in Taiwanese Southern Min as conjunctions, which spans 3,500 years. A process of polygrammaticalization took place already in the 5th century; the adverb gòng 共 developed the functions of both an AND conjunction and a WITH preposition. Since the end of the 14th century, the Southern Min kang7 共 became a function word of CONJ and PREP. In addition, the AND conjunction changed, renewed and diversified into other categories.