先秦漢語語法仍有不少難解問題，句末語氣詞是其中之一。句末語氣詞註記言說主觀性，出示說話人的發言立場與態度，功能相當抽象；而帶句末語氣詞的語句經常延伸出依附於語境的表達作用，使得句末語氣詞是否賦有單一的規約化功能備受質疑；加上以往研究使用的術語分歧，更讓後來研究者感到困惑。本文嘗試跳脫術語羈絆，回到句末語氣詞賴以成立的概念依據，區辨先秦語氣的類別並闡述功能引申及其可能導致的歷時演變。文中指出表述主觀意願之語句成分和句末語氣詞所傳達的主觀性的差異，也指出先秦有少數的句末語氣詞，功能已然從主觀性跨入交互主觀性。從主觀性詮解漢語句末語氣詞是當前新趨勢，有別於過去的研究視角；本文基於主觀性為先秦句末語氣詞提出初步的功能分類及演變假設，可為後續研究的參照。

Sentence-final particles of modality (hereafter “particles”) are among the most problematic aspects of pre-Qin Chinese grammar. Previously, scholars agreed that these particles by convention designate the subjectivity of an utterance, i.e., the speaker’s vantage point or attitude. However, the sentences in a discourse that end with such particles often shift in their expressive force depending on context. This raises the question whether the particles are multifunctional in nature, rather than each possessing one single conventionalized function. The issue has been further complicated due to terms being inconsistently used in previous studies. By relying instead on a conceptual basis for particles, the present paper attempts to distinguish their functional categories and to explain how contextual factors may have had an impact on the use of particles and consequently resulted in diachronic change. This paper identifies differences between the subjectivity implied in the predicative components of a sentence and that designated by particles, and also makes the point that the subjective function of a couple of the particles might have already crossed over into inter-subjectivity. In explaining sentence-final particles of modality in Chinese from the point of view ofsubjectivity, this paper follows the current trend in linguistics for approaching these issues, a departure from previous studies.