the effect of lexical collocational density on the iranian efl learners’ reading comprehension

the present study aims at investigating the effect of different levels of lexical collocational density on efl learners’ reading comprehension. eighty sophomore students with different levels of proficiency studying at  zand institute of higher education in shiraz, iran were chosen from among eighty five learners based on their score distribution on a reduced toefl test constructed by educational testing service (ets, 1998). forty participants were randomly assigned to the control group, while the other forty made the experimental group. another instrument used in this study was a lexical collocation test containing two texts (as pre- and post-tests): a high and a low lexical collocational density tests designed by the researchers. a few paired/independent sample t-tests, and a two-way repeated measure were used to answer the five research questions. results indicated that texts with high lexical collocational density influenced learners’ comprehension positively. although the instruction of lexical collocation did not have any effects on answering the vocabulary items significantly, teaching lexical collocations affected learners’ reading skills positively. finally, different proficiency levels of the participants did not affect their performance on lexical collocation test with different lexical collocational density significantly.