This study investigates phraseological complexity development in the writing of French learners of English as a Foreign Language from the Longitudinal Database of Learner English (LONGDALE). More particularly, it examines the effects of proficiency and time spent learning English on the phraseological sophistication of verb + object relations, which is measured with mutual information at three data collection points. Results of a mixed-effects model in which we control for potential effects of topic/prompt show that learner proficiency, as assessed by a standardized test, is a better predictor of phraseological complexity in each learner writing sample than the actual data collection point at which the essay was written, thus suggesting that the time dimension does not add anything to, or modify what we already know about, EFL learners’ use of statistical co-occurrences as represented in this longitudinal corpus.

This study investigated the long-term evolution of lexical diversity of adult L2 learners of French and Spanish (n = 33) over a five-year period. A longitudinal learner corpus was collected that includes oral (semi-structured interview, picture-based narrative) and written (argumentative essay) data. Three data collection waves are investigated in the current study: (a) before learners studied abroad as part of their university degree program, (b) at the end of their nine-month stay abroad, and (c) three years post-instruction. In addition to examining the potential outcomes of attrition, maintenance, or development, this study explores the extent to which variables such as peak attainment and language exposure/use predict changes in lexical diversity three years post-instruction. Results of ANOVA analyses indicate continued improvement in lexical diversity post-instruction for oral but not written tasks. Regression analyses indicate that both peak attainment in lexical diversity and language exposure/use contribute significantly to predicting gains in lexical diversity post-instruction on both oral tasks, with peak attainment explaining more of the variance than language exposure. The findings help us better understand the variables that influence the long-term evolution of foreign language proficiency after the conclusion of formal instruction.