一般而言，國際學校的華語教師，把學生習得華語時的雙語或多語語言轉換，視為語言習得的必然現象。此種思維不完全同於Selinker所提的中介語理論下的正、負遷移、偏誤與石化內涵。本研究的目的，即在於透過兩所個案國際學校的華語雙語習得規劃調查，以檢視中介語理論概念在國際學校華語雙語習得課室裡的理論典範意義。這是一個以質性為主量化為輔的研究，研究者於2010年八月至2012年七月間，在曼谷及高雄各選一所國際學校為個案。課室觀察田野筆記與開放式訪談為主要之資料來源，次要資料則是文件檔案與基本背景資料問卷調查。透過編碼、定義、比較、分類與歸納等方式，研究者交叉檢證個案國際學校華語習得現象之異同，並回答預擬之研究問題。研究發現，因為華語課室的語言遷移，是在三至四種語言之間動態的進行，所以，並無正、負遷移的價值判斷意涵。再者，單語表現不是評定華語能力的最重要標準，所以，偏誤及石化現象也不必然是學生華語能力的判準依歸。研究者因此建議，當前華語教學領域有必要重新思考與修正傳統中介語理論在各類華語習得場域裡的典範性，因為傳統概念之正、負遷移、偏誤與石化內涵，並不完全合適用於解釋國際學校華語課室裡的雙語習得多元現象。

Generally speaking, Chinese teachers in international schools view bilingual or multilingual translanguaging while students acquire Chinese as an inevitable phenomenon. However, this thought is different than the Interlanguage theory (Selinker, 1972), which states ideas of positive and negative transfer, error, and fossilization. The purpose of this study is to examine the ideas from Interlanguage theory through classrooms of Chinese bilingual acquisition planning in two international schools. The major method of this case study was qualitative and quantitative data was also included. Two international schools in Bangkok and Kaohsiung were invited to participate. The study began from August, 2010 and ended in July, 2012. Data collection was mainly from classroom observation fieldnotes and open-ended interviews. Documents and survey of background information questionnaire were also used as minor sources. In terms of data analysis, the researcher encoded, defined, compared, classified, and generalized the whole data and then cross checked the differences and similarities of Chinese bilingual acquisition phenomenon between two international schools. Research findings were then synthesized to answer the proposed research questions. The researcher finds that in many Chinese classrooms, students who are acquiring Chinese usually transfer among three or four languages dynamically. Hence, the implication of differentiating positive or negative language transfer is not workable in the cases. Furthermore, students' monolingual performance of Chinese is not the standard to assess their Chinese proficient level. Chinese errors and fossilization are not the main criteria to evaluate students' Chinese performance, either. Based on those findings, the researcher suggests that ideas of positive and negative transfer, error, and fossilization, which have been discussed in traditional Interlanguage theory, are not applicable to interpret the Chinese bilingual acquisition phenomenon in international schools. In the current field of teaching Chinese as a second/foreign language, it is necessary to re-consider and modify its traditional paradigm of Interlanguage theory to meet the diversified linguistic facts.