本文從「到₃」用法較為多元的《客家社會生活對話》語料出發，探討前賢學者已經有所著墨的「到₃」、「到₅」功能的重疊與分工，並且較詳細的描寫臺灣客家話相關用法的情況。文中一一探討這些成分作為帶趨向終點的動後成分、動相補語、傀儡可能補語、完成體標記、持續體標記及狀態或程度補語標記的用法。在此基礎上，本文探討兩個相關的問題：一是「到₃」的本字問題，二是「V到3來」與「V到5來/去」的語法、語義性質。

Based on data from Conversations Chinoises Prises sur le Vif avec Notes Grammaticales: Langage Hac-Ka, of which the postverbal taò has quite diverse usages, this article discusses the parallel and distinguishing functions of taò and taó, which have been explored by some accomplished scholars previously; furthermore, the related usages of taò and taó in Taiwan Hakka are discussed and compared thoroughly as well. The functions of postverbal goal marker, phase marker, dummy potential complement, perfective marker, durative marker and manner or degree complement marker, which taò and taó can act as, are discussed respectively in this article. In addition, there are also some notes on two related issues: the etymology of taò, and the syntactic and semantic characters of 'V taò loi2' and 'V taó loi2 /hi5'.