From 'two' to a comitative-instrumental case marker A regional innovation in the Gansu-Qinghai linguistic area

This paper examines the comitative and instrumental case markers in the Chinese dialects and Altaic languages spoken in the Gansu-Qinghai Linguistic Area (GQLA) and finds a noteworthy phenomenon: one of the frequently used comitative-instrumental markers originated from the numeral 'two', a rare source for comitatives. The numeral 'two' is grammaticalized under the process of {'two' (appositive) > coordinator > comitative > instrumental}. This paper argues that the marker 'two' in Chinese dialects did not have an Altaic origin and was then borrowed for Chinese, as Dwyer (1992) suggested. The fact that the comitative-instrumental markers in both Altaic (especially Mongolic) languages and Chinese dialects come from the numeral 'two' with comitative-instrumental syncretism reflects a regional innovation in GQLA.