The Relationships between Lexical Sophistication and Second Language Writing and Speaking

The Relationships between Lexical Sophistication and Second Language Writing and Speaking

This study examines the relationship between lexical sophistication and the scores of second language (L2) persuasive writing and speaking. The dataset included 120 essays and 120 speeches produced by university-level learners of English as a foreign language. The essays were written as persuasive texts, while the speeches involved dialogues where learners were required to persuade their listeners. Lexical sophistication features were analyzed based on word frequency, psycholinguistic properties (i.e., concreteness, imageability, and age of acquisition), and word associations. Regression analyses revealed that word association scores were the strongest predictor for both L2 writing and speaking score, emphasizing the importance of the word association dimension of lexical sophistication across modalities. The model predicting L2 writing scores showed that higher-rated persuasive essays contained more low-frequency content words and words with restricted contextual usage, explaining 15.8% of the variance in writing scores. The model predicting L2 speaking scores found that higher-rated persuasive speeches included more words with restricted contextual usage, explaining 26.4% in speaking scores. Overall, these findings suggest that while word associations are broadly important, specific lexical features such as frequency and contextual restrictions play varying roles in different modalities of L2 persuasive tasks.