It is widely acknowledged that collocations play a crucial role in second or foreign language learning by enabling learners to know more about language chunks and lexical strings. Although many studies have examined L2 learners’ collocational competence, comparatively less research has been carried out to probe into the effective instruction and exercises for enhancing the acquisition, retention, and production of lexical (e.g. make a mistake ) vs. grammatical ( on purpose ) collocations. Therefore, the present study attempted to explore the effect of L2 definitions, fill-in-the-blanks, and sentence writing exercises on the acquisition, retention, and production of lexical vs. grammatical collocations. The data were collected from 66 EFL participants who were studying English at a private language institute. First, an Oxford Placement Test (OPT) was given to homogenize the learners. Then, the participants were divided into three groups, each receiving one of the three different types of exercises including definitions, fill-in-the-blanks, and sentence writing exercises. Data analysis using multivariate ANOVA (MANOVA) indicated that learners who received the sentence writing treatment significantly outperformed those learners who received definition and fill-in-the-blank exercises in the acquisition, retention, and production of lexical vs. grammatical collocations. Moreover, fill-in-the-blanks could help the participants learn, retain, and remember both types of collocations significantly better than the L2 definitions. These findings have some pedagogical implications for learning and teaching lexical and grammatical collocations.
