本文討論臺語一些虛詞的語意變化的方向動力。研究目的不在於過去虛詞擬古，而在於現在語言現象可以觀察到的語言變化動向。方法上採用同一語意範疇各語詞間的語層先後、記憶方式（詞匯、詞法、句法），以及語言風格等資料觀察虛詞語意變化的動向和動因。可以看到同議語間的共存、競爭、分工中幾種動力互動的的動向是：觀念結構上的語意精密化，表意明確化，記憶認知上的效率化，風格上簡、繁多樣化。 Paul Kay（1977）觀察到隨著語言使用社區由原始社會演進到現代社會，言談風格（speech style）也跟著變化。現代社會裡不同的語言使用場合、不同的社會背景的人，也有不同的言談特點。很多臺語同議語、類義語之間可以分先後，借此探討不同的風格功能的動向。又有很多臺語同義語、類義語之間可以分鄉土的、廣通的、混合的，借此也可以探討不同的風格效果的動向，又可分為詞匯、慣用語型、一般句法等三種不同的記憶認知方式的語詞處理策略。這些動向，是人類隨著時代進展而有的共同變化特點，而不是臺語特有的。必定有人類腦神經結構及社會自然律的基礎。臺語裡豐富的同義語及高比例的多語人等現象極有利於從事有關的課題研究。 不同語法結構裡的虛詞語意動向分為三類討論：(2.1)語義受外來影響而觀念精密化表達明確化的同義虛詞。（連接詞遞增絛件、量詞結構的發展和「每、逐〔tiok〕、各」、程度副詞），(2.2)語義沒有因外來影響而精密化的虛詞（反詰問句的虛詞、四種表條件的副詞「就、才、嘛、愈」之間的語意對立、無效條件句裡「嘛、攏、都、也」的中立化）及(2.3)因常用觀念特別記憶方式而有特異現象的虛詞。 本文將特別注意英語不太類似、語言學界不去注意、或是有爭論的語法現象。如：全指語（全部範圍語）都需要前移（move）到謂語副詞「嘛、攏」之前。任指語（〔無論〕QW），以及反常指（〔連〕一個、〔連〕卡、〔連〕閣卡、〔閣〕偌、甚至〔連〕N，〔連〕N）也都需要前移到謂語副詞「嘛、攏、都、也」之前，同時形成條件形式，表無論在任何條件或反常條件下，結論都不變的（無效條件句）。這和英語的句法是很有趣的對比。英語的WH需要前移（到句首），漢語並不需要。漢語的全指、任指、反常指需要前移；英語的all，whatever，even卻不需要前程。這種異同使語言類型和語言理論的研究更加有意義。 條件句的前題標準是英、日語的特點。臺語所用虛詞（如果、著愛、無論、連、甚至），受外來的影響很大。語意變化很多，有不少同義詞，又可以省略不出現，結果語的標誌是臺語的特點，「就、才、嘛、攏」等連結副詞，不受外來影響。無效條件句所用的結論子句虛詞「嘛、攏、都、也」語意中立。類似現象在臺語特別多，在探討語言變化動向的方法和理論上有幾個重要意義。 一、 漢語依靠語型來決定語詞間語意關係的情況比英語多。虛詞常常被省略，詞匯語意也常常因context而改變。 二、 要處理這種因上下文而決定語意的漢語語法，需要掌握特列慣用語型，列在一個模組裡，標誌其語意，並列出其規律句法的對等結構。 三、 規律句法的對等結構在各自然語言間很類似。慣用語型就互相不很類同，連華、臺之間，也不少差異。

　　　　　The paper discusses the changing forces and their interaction in the meaning of some Taiwanese function words. Synonyms are categorized in terms of chronological order of language layers, memory units (lexical, morphological and syntactic), stylistic effects in order to observe the trend and forces of change. Among the forces to co-exist, to compete, and to readjust in functions, the trend of change is to move toward semantic refinement, clear manifestation, effectiveness in memory and stylistic versatility. Paul Kay (1977) has observed that speech style of a language changes as the society evolves from a primitive society to modern. Even in the modern society, speech style varies according to life contexts and the social back-grounds of the speakers. Taiwanese has abundant synonyms which can be arranged into the chronological order, and thus provide clues to the direction and motivation of language change. Chronological ordering is determined through dividing the synonyms into common, unique and mixed, and three types of memory unit, lexical, more phological and syntactic and through examining their reading layers (colloquial is earlier than literary) and comparison with Classical Chinese and Mandarin. (those with no match being the earliest, those matching with a Classical Chinese word the second, and those matching one in Mandarin the latest.). Function words are divided into three types: (2.1)those that have become more semantically refined as a result of borrowing. (2.2)those that have not been affected by outside influence. (2.3)Those that have acquired or retained special meaning only in a given idiomatic pattern. The paper focuses on grammatical phenomena that are strikingly different from English. Totality and multiplicity quantifiers move foreward (or upward) to precede their distributive adverb ma 'also' or long 'all'. Distributive bo-lun Q 'no matter WH-' and the unexpected conditional lian 'even' NP or clause, also has to move to rpeced their adverb 'ma. Long, to, ia' denoting to change in the conclusion. By contrast, English 'all, 'whatever', or 'even' expressions are not required to move. On the other hand, WH-movement is required in English, but not so in Taiwanese (nor in Mandarin and Japanese). Marking the premise portion of a conditional is a characteristics of English and Japanese grammar, whereas Taiwanese may redundantly mark both the premises and the conclusion. Taiwanese has imported many conjunctions for premises resulting in a large amount of synonyms and refinement of meanings. Obligatory marking the conclusion portion with a conjunctional adverb is a characteristic of Taiwanese grammar. This type of adverbs have had few borrowings from external sources and have hardly changed their meaning. In investigating the meaning of function words, the paper offers the following points concerning idiomatic constructions. (1) Han languages have more cases of relying on constructions for meaning than English, since function words are often deleted or undergone change of meaning. (2) It is best to treat the meaning of an idiomatic construction by listing it in a module where its meaning is marked. (3) Languages tends to share similar features of regular syntax, but not so in idiomatic constructions. Even between Mandarin and Taiwanese there are quite a few differences.