中文摘要：

对《太平经》方所介词进行了定量统计,将其与上古和中古时期其他专书的方所介词系统进行比较,观察方所介词系统的变化,方所介词系统的功能是逐渐完备的。＂一个介词兼有多种功能,一种功能由多个介词承担＂的特点正在淡化。常用介词＂於＂的使用频率大幅下降,其介引所从处、所在处、终到处的功能逐渐被新兴介词侵蚀,＂在＂、＂从＂逐渐成为常用介词。中古新兴介词用例不多,使用频率也不高,但其功能单一的优势让它们在竞争中逐渐占据上风。

英文摘要：

The article did quantitative statistics of position prepositions in Tai Ping Jing,and compared its position preposition system with those in other specialized books in ancient times and mediaeval times,to show the changes in time preposition system. The function of position preposition system is gradually completed. The original character that one preposition had more than one function and one function could be conducted by more than one preposition was gradually diluted in the mediaeval times. The usage frequency of the preposition yu（ 於）,which was widely used,drops greatly. And its functions of introducing the start point,the current position and the end point were gradually taken place of by new prepositions. As a result,zai（ 在） and cong（ 从） were then commonly used. The actual samples and usage frequencies of new prepositions were quite limited,but their advantages of unitary function help them occupy the predominant position later.