語言是一個不斷變動的結構，而造成語言結構改變的原因，一般可分為兩種情況下進行；一為語言內部的分化；一為外部的、語言間或方言間的接觸。在傳統的歷史語言學的研究上，大多只偏重於語言內部自身的變化，而忽視了語言間因彼此接觸所造成的影響，但自從王士元提出「詞彙擴散」理論，證實了「語音的變化是突變的，詞彙的變化是漸變的」的原理之後，語言接觸的問題，逐漸受到學者的重視。董忠司師則更進一步，在語言接觸所形成的語言變化與類型上，提出「取代型」與「新變型」兩大類型。董忠司師的語言接觸模型，展現了二種不同語言在發生語言接觸時的演變進程，本論文將此模型為基礎，以宜蘭縣的閩南語為例，來觀察此模型是否適用於實際語言的情形。

Language is a structure that keeps changing. Generally speaking, the reason why language structure changes is language inner divergence and contact between languages or between dialects. In traditional historical linguistic research, changes within language itself are more emphasized, but the influence of contact between languages is ignored. However, since Wang, William S-Y (王士元) to bring “lexical diffusion” which brought out the principle of “Sound change takes place in a few words and then spreads successively to all words concerned.”, Language contact is more and more noticed. For language contact causes language change, Tung Chung-szu (董忠司) brought out two kind of language change: one is generation style (取代型) and the other is change style (新變型). Tung Chung-szu's model of language contact shows two kind of process of changing when languages contact. Based on this model, here I take Southern Min dialect of Yi-lan for example to observe the actual situation of language.