| This paper aims to discuss and explore the usage of prepositions of Chu and Qin by taking eleven bamboo slips as research materials. In ancient Chinese, prepositions like "于(yu) ”,“於(yu) ”,“以(yi) ”,“与(yu) ",“及(ji)" are of relatively high frequency of use,"于"(yu) and "於"(yu) in particular. With multiple semantic functions,the two prepositions can be used to indicate location, time, object, range and means. Although "于"(yu) appeared earlier than "於 "(yu),the two words of different origins can be considered as the same type of function words regardless of their minor differences in usage. In Chu and Qin bamboo slips,"於" (yu) has a dominant advantage in usage, and there is an decreasing trend in use of "于" (yu) in Qin bamboo slips, which implies that the semantic function of "于"(yu) had been replaced by "於"(yu)gradually. Likewise,the preposition "以"(yi )also has multiple usages,which can refer to means,cause,time,object,etc.. It has great flexibility in composing with other words in collocations like “何以”,“此以”,“是以”,“所以”,“有以”,“无以”,“足以”,“以A为B” and “以为”.Both“与”(yu) and “及” (ji) can be used as either prepositions or conjunctions,complementing each other in usage also in bamboo slips. In Chu and Qin bamboo slips,“与 ”(yu) is often used as preposition,though more frequently in the latter. However,“及”(ji) in Chu bamboo slips outnumbered that in Qin bamboo slips,mainly used as time preposition. There were only two cases of referring “及” (ji) to object in each of the two types of bamboo slips. In terms of their conjunction usages,“与 ”(yu) is more frequently used in Chu bamboo slips,while “及”(ji) is more widely accepted in Qin bamboo slips. |