This study examined n-gram use in oral production by Chinese college-level English as a foreign language (EFL) learners at four distinct proficiency levels. Thirty indices regarding range, frequency, and association strength of bi- and tri-grams obtained from retelling and monologic samples were analyzed. Results suggest that, i) the four proficiency levels differed in measures for frequency and association strength of bi- and tri-grams, ii) academic bi- and tri-gram proportions and association strength (captured by MI- and t-scores) were predictive of EFL speaking proficiency for both the retelling and monologic samples but the effects were small, and iii) EFL learners used more well-attested bi- and tri-grams in monologues than in retelling, demonstrating that higher rated samples tended to contain more strongly-associated bi- and tri-grams, a greater proportion of frequent attested academic tri-grams, and that EFL n-gram use was task-sensitive. These findings help enrich our understanding on EFL development of multi-word sequences and have potentially useful implications for EFL pedagogy.