Language performance requires efficient use of knowledge of the target language on line. Use of linguistic knowledge directly affects the process and the product/result of performance, potentially impacting on development of general language proficiency. Developmentally speaking, there is an interdependent and reciprocal relationship between linguistic knowledge and general language proficiency (L2) (e.g., Anderson & Freebody. 1981; Laufer, 1997: Nation & Newton, 1997; Paribakht & Wesch, 1997; Qian, 2002). Yet, little has been investigated about this relationship in the JSL context. There is also some growing evidence that an individual's fist language significantly influences L2 development and process (e.g., Kellerman & Sharwood Smith, 1986; Koda, 1986; Ringbom, 1986, 1987). Yet, the effects may not be detectable in learner performance because general language tests do not provide information about how different aspects and dimensions of linguistic knowledge develop and are related to language proficiency.
In this research we investigated the development of TL knowledge and its relationship to reading proficiency in intermediate-advanced Japanese-as-second-language (JSL) learners with different L1 backgrounds. Study 1 was designed to examine Chinese- and English-speaking students (N=98) in terms of developmental profile of linguistic knowledge (vocabulary and grammar) and its relationship to reading. Study 2 was to examine Chinese- and Korean- speaking students (N=86) in terms of development of different dimensions of vocabulary knowledge (breadth and depth) and its relationship to reading. The items used in the vocabulary and grammar tests were rated for frequency (i.e., level of difficulty) based on the Japanese Language Proficiency Test (Nihongo Noryoku Shiken). Data obtained from native speakers (N=86) were used as Baseline. Based on the results of ANOVA and regression analyses, we will discuss the developmental profiles of linguistic knowledge and its relationship to reading performance in these JSL learners, and draw implications for curricular and instructional intervention to meet increasing learner diversity.