Abstract
The article amounts to a fully comprehensive study on the sentence final particle ěr 爾 in Classical Chinese. After an overview of the explanations of the functions of the particle in reference books, all relevant occurrences in the pre-Qín texts are analysed, and the results are compared with its usage in the documents of the Western Han era.
The possible interpretations of its meaning(s) proposed by the author are subsequently put in relation to hypothetical etymological links based on the theory of Old Chinese morphology in Sagart's vein.