本篇論文是針對六位以台灣華語為母語的嬰幼兒，採長期觀察的方式，研究 台灣華語字彙產製的音韻變化性(phonological variability)，並詳細描述單音節詞和雙音節詞之中音節類型出現的頻率、變化性、以及代換模式。本研究同時要用Jakoson (1968)的音節標記理論來檢驗各種音節類型中的共通性。 本研究一共觀察了有六位年齡在十一個月至兩歲的嬰幼兒長達一年。以兩個 禮拜一次的頻率收集嬰幼兒和母親之間的自然對話，並利用錄製回來的影音檔做 譯寫和分析。 結果顯示小朋友的音韻變化是很常見的，且是有規則可循的。小朋友的音韻變異量的高峰(variability peak)會出現在當小朋友的音韻發展從一個階段進展到另一個階段的時候，而本篇論文顯示與當小朋友由單字期(one-word stage)進展到雙字期(two-word stage)以及字彙量有大幅上升的時期符合。華語音節習得的部分，結果顯示CV 是頻率最高、變化性最低，且最常被拿來替換的音節類型。CVG 也是頻率高的音節類型之一，但他的變化性也很高，主要是因為韻尾省略 (coda-dropping)的現象在小朋友的早期發展很常見的關係，所以CVG 雖然頻率高但是變化性也很高而且是最常被取代的音節類型之一。 最後，將所有的結果拿來檢驗Jakoson (1968)的音節標記理論，結果發現頻 率高以及變化性低的音節類型都是無標記(unmarked)的音節類型，相反的頻率低 以及變化性高的音節類型則都是有標記的(marked)音節類型，此外小朋友會用無 標記的音節類型來取代有標記的音節類型。 / The purpose of this study is to discuss the issue concerning phonological variability of children acquiring Taiwan Mandarin. Two aspects are including in the following: the phonological variability of words and the syllable types composed the words. The overall variability pattern, the frequency, variability rate, and substitution pattern of syllable type were analyzed. Six participants are investigated in the study, aged between 0;11 to 2;0. A longitudinal observation study is conducted by the author and the research team. The results showed that phonological variability is common in early phonological development. The increase in variability reflects the reorganization of phonological system, where children started to produce two-word utterances and the amount of different words was increased. As for the syllable type analysis, CV presented the highest in frequency, the lowest in variability rate, and also was used to replace other syllable type more often. CVG was one of the most frequently used syllable type; however, the variability rate of CVG was also high. The reason may due to the fact coda-dropping is a very common phenomenon in children’s development. The results in this study were examined in the markedness theory of syllable proposed by Jakobson (1968). The results showed that syllable types with higher frequency and lower variability rates were unmarked syllable types, while syllable types with lower frequency and higher variability rates were marked syllable types. Furthermore, children tended to use a more unmarked syllable to replace a more marked syllable.

國語二聲在文獻上多被描述為一調值35的高升調。然而近來不少學者發現台灣地區的國語二聲在閩南語/國語雙語語者族群中有變異的現象：一是323的降升調，二是接近31的低降調。文獻顯示這可能與語言背景(Lo, 2004)和地區(H. J. Hsu,2004)有關。然而對於國語單語語者的研究並不多。此外，性別、母音、聲調環境和句中位置也有可能影響聲調的變異。因此，本研究旨在調查台灣地區的聲調變異現象，藉由語音學實驗的方式，探究國語二聲的變異和語言背景（閩語/國語雙語語者或國語單語語者）的關係。並進一步探討其與社會因素：地區（北、中、南）、性別和語言學因素：母音、聲調環境和句中位置的關係。受試者以17-27歲的年輕族群為主。結果發現台灣地區的年輕人普遍以平調（中平調或低平調）(level)作為二聲變異的主要變體，另一較少數的變體則為低升調(low-rising)，低降調在本研究中並不明顯。這些二聲變體有可能是受到整體調域向下縮窄的影響。而閩語/國語雙語語者的確發出較多的聲調變異，特別是低升調，這可能是受到閩語聲調系統的影響。地區、性別，以及母音、聲調環境和句中位置都會影響二聲變異。本研究進一步證實二聲的聲調變異在台灣年輕族群中的發展，支持了台灣地區國語的調域縮窄的現況。 / Mandarin Tone 2 is canonically described as a high rising tone. However, recently, T2 in Taiwan was found to have other contour types: the dipping contour (323) and falling (31) variants (Fon, 1997; H. J. Hsu, 2004), with the former being considered as a normal rising tone, but the later totally losing the rising feature. Those were all found in Taiwanese (Tw)-Taiwan Mandarin(TM) bilinguals. The reasons causing this tonal variation is supposed to be relating to the language backgrounds and other social and linguistic factors from previous studies. However, no study has confirmed those correlated factors, especially the comparison between Tw-TM bilinguals and TM monolinguals. This study thus aims to discover what the T2 variation is and where it occurs. By sampling 24 subjects, aged 17-27, with half Tw-TM bilinguals and half TM monolinguals, we conducted three experiments to test the T2 in different contexts. Results showed that instead of the falling variant, more speakers produced a level variant and a small amount of low-rising variant. Besides, the bilinguals did produce more T2 variations than the monolinguals. The results indicated that language background does affect the T2 variation among young speakers in Taiwan. Moreover, the high percentage of the Level variant support the finding of a narrower tonal range of TM, compared to the standard Mandarin. Other factors, such as genders, regions, vowels, tonal environments and sentence positions were also found to have influence on T2 variations.