The Effect of Vocabulary Knowledge and Background Knowledge on Reading Comprehension among Non Iranian Persian learners

Comprehension is the process of getting information from reading and listening. It plays a fundamental role in language learning. Several factors are involved in comprehension such as vocabulary knowledge and prior/ background knowledge.
This research investigates the effect of lexical knowledge and prior knowledge on the understanding of non-Iranian Persian texts. The participants of this study are multilingual learners.  For this purpose, out of about 100 advanced language learners of the Persian language teaching center of Imam Khomeini International University in Iran, 65 (of both genders) were selected. After homogenizing the participants by a word level test, they were reduced to 46 (sample population). Subsequently, this number was divided into two groups of 23 learners, vocabulary training and activating the previous knowledge. A pre-test was held including two reading comprehension passages focusing on culture and history of Iran. The reliability of the test was analyzed based on Kooder-Richardson and the result was 0.71. Both groups were taught the unfamiliar words of the test and finally the same test was conducted as a post-test. The pre-test and post-test results of the two groups were analyzed using ANOVA, paired sample t-test and Kolmogorov-Smirnov tests. The results of the data analysis in relation to the research hypotheses is summarized as follows:
The first hypothesis of the research focused on the influence of lexical knowledge on the comprehension of reading passages of non-Iranian Persian speakers. The results of the data analysis confirm the first hypothesis with a high level of significance. This result is in line with the results of the Anjomshoa and Zamanian(2014), Zhang and Annual (2008), Rashidi and Khosravi (2010), Shiotsu and Weir (2007), Golkar & Yamini (2007) and Mehrpur et al. (2011). The second hypothesis focused on the effect of prior knowledge on the comprehension of the reading passages of non-Iranian Persian learners. The results of the data analysis indicated that the activation of previous knowledge does not have a positive effect on the comprehension of  the passages. The results of the previous studies in this area, unlike the effect of lexical knowledge on reading comprehension, are not homogeneous, and different results have been obtained. The results of this study also indicate that the activation of prior knowledge on reading comprehension sometimes does not have any positive effects. Moreover, it can sometimes be influenced by factors such as the complexity of reading text and the lack of familiar vocabulary.
Finally the findings of the research suggests that the lexical knowledge of non-Iranian Persian speakers has a greater impact on reading comprehension than their previous knowledge.
This study has the following implications. First, language teachers should pay more attention to the choice of reading passages.  The reading passages should not only be look at as a practice, but these passages should be for the acquisition and improvement of knowledge. By choosing textbooks and reading resources appropriately, learners will be able to effectively enhance their lexical knowledge and general information.
Second, teachers should find ways to increase lexical knowledge. For example, encourage learners to read texts beyond textbooks. And in the end, the findings of this study indicate that vocabulary plays a very important role in reading comprehension. Therefore, teacher should spend more time on activating learners’ lexical  knowledge in the form of sentence building, expressing the synonyms and opposites of the words, and explaining unfamiliar words.