| Although studies of lexical inferencing indicate that second language learners frequently encounter difficulties inferring lexical meaning from context, lexical inferencing, or deriving lexical meaning from contextual analysis, constitutes an essential part of reading comprehension. Two main purposes motivated the current study. The first purpose was to investigate how 139 Japanese EFL learners performed in lexical inferencing tasks and the second purpose concerned to what degree their linguistic and extralinguistic knowledge sources were related to lexical inferencing and which knowledge sources contributed to successful lexical inferencing. Linguistic knowledge sources were categorized into lexical knowledge (recognition vocabulary and collocation), syntactic knowledge (syntactic property of words and sentence-level grammar), and discourse knowledge of cohesion and coherence (conjunction, pronoun reference, and discourse prediction). Extralinguistic knowledge sources concern background knowledge related to the topic of texts.;The participants were relatively successful at the lexical inferencing tasks for two reasons. First, the lexical density of the texts was controlled so that almost all of the non-target words were at the 2,000 word frequency level, a comprehensible level for the participants in this study. Second, the data were analyzed in a way that gave the participants credit for acquiring partial knowledge of the semantic features of the target words.;All the knowledge sources were significantly correlated with lexical inferencing, and a hierarchical multiple regression identified the three best predictors of lexical inferencing. Discourse prediction was the best predictor of lexical inferencing due to the similarities of the cognitive processes of bridging information gaps through scrutinizing textbase input. The second best predictor was written receptive vocabulary size, the most fundamental component of deriving meaning in a text. It was followed by text-related background knowledge. Other significant, but minor predictors were knowledge of the part-of-speech of words and syntax, both of which are constituents of sentence-level processing. Collocational knowledge and knowledge associated with discourse-processing constituents were not significant predictors of lexical inferencing.;To summarize, three semantically oriented knowledge sources, i.e., discourse prediction, recognition vocabulary, background knowledge, were more important predictors of lexical inferencing than structurally oriented knowledge sources such as part-of-speech and syntax. |
