The multidimensionality of second language oral fluency: Interfacing cognitive fluency and utterance fluency

The current study examined the extent to which cognitive fluency (CF) contributes to utterance fluency (UF) at the level of constructs. A total of 128 Japanese-speaking learners of English completed four speaking tasks-argumentative task, picture narrative task, reading-to-speaking task, and reading-while-listening-to-speaking task-and a battery of linguistic knowledge tests, capturing vocabulary size, lexical retrieval speed, sentence construction skills, grammaticality judgments, and articulatory speed. Their speaking performance was analyzed in terms of speed, breakdown, and repair fluency (i.e., UF), and scores on linguistic knowledge tests were used to assess students' L2 linguistic resources and processing skills (i.e., CF). Structural equation modeling revealed a complex interplay between the multidimensionality of CF and UF and speaking task types. L2 processing speed consistently contributed to all aspects of UF across speaking tasks, whereas the role of linguistic resources in speed and repair fluency varied, depending on task characteristics.