本文運用方言本字研究的尋音、探義等系統性方法，深入探究閩語既表 意志義、又表即將義之語詞的歷史來源與發展演變。該語詞在閩南方言讀為 bəʔ4∕beʔ4∕bueʔ4，在閩東方言主要讀為puoʔ4。從方言歷史音韻規則來看，該 語詞嚴整對應於漢語詞「發」；然而，閩南方言beʔ4、閩東方言puoʔ4 在語義、 語法發展方面如何合理聯繫為漢語詞「發」，此為本文著力討論的課題。 本文首先辨析古漢語文獻資料中「發」的各種語義及用法，探求「發」由 主要動詞進而虛化的語義、語法基礎；接著透過具體語料的蒐集彙整，分析閩 東方言puoʔ4、閩南方言beʔ4 的各種語義用法，並提出該語詞相當關鍵的兩 大語法特點；最後，參照古漢語表未來時「將」的語法化過程，以及跨語言對 於未來時態標記的研究成果，重新推論閩東方言puoʔ4、閩南方言beʔ4 的語義、 語法發展脈絡，以確立該語詞與漢語詞「發」的同源關係。

In this paper, I compare the boulomaic modal and prospective aspects of the words “beʔ4” in Southern Min and “puoʔ4” in Eastern Min and differentiate the sound correspondences between Min and ancient Chinese. Based on the sound correspondences, I hypothesize that the Chinese cognate words “beʔ4” and “puoʔ4” should be “fa ( 發)” and then prove this hypothesis with the following three methods. (1) I trace the process of the impending grammaticalization of “fa ( 發)” in archaic and ancient Chinese books. (2) I analyze the meanings and usages of the words “beʔ4”and “puoʔ4.” I find out two grammatical features of them: (a) “beʔ4”and “puoʔ4” are used not as the main verbs in sentences but only as boulomaic modal auxiliary verbs; (b) it is prohibited to place negative words in front of them. (3) I make a connection between “beʔ4,” “puoʔ4” and “fa ( 發)” by referring to the grammaticalization of “jiang ( 將)” in archaic Chinese and cross-language researches of the future tense.