TY - JOUR T1 - An Analysis of the Development of lexical cohesion in Persian -Speaking Students’ Written Discourse TT - بررسی و تحلیل رشد ابزار انسجام واژگانی در گفتمان نوشتاری دانش آموزان فارسی زبان JF - mdrsjrns JO - mdrsjrns VL - 8 IS - 1 UR - http://lrr.modares.ac.ir/article-14-8899-en.html Y1 - 2017 SP - 179 EP - 205 KW - written discourse KW - Functional grammar KW - Students KW - Lexical cohesion N2 - This research aims at analyzing and comparing the development of lexical cohesive devices (repetition, collocation, synonymy, hyponymy, meronymy) in Persian-Speaking students’ written discourse at primary level (9 to 12 years old) according to logical meta-function introduced in Halliday and Mathiessen’s systemic functional grammar (2004). Descriptive analytical method is used in this study. 45 students (boys) studying at primary school (4th, 5th and 6th grades) in 1393-94 have been selected through random-sampling. Two written tests in the form of picture stories were administered for gathering the written data. Frequency, percentage and pattern of development of using lexical cohesive devices were compared and analyzed. The frequency of lexical cohesive devices in 4th, 5th and 6th grades were, 862, 967, and 1119. Repetition and collocation in all grades are the most frequent and hyponymy and meronymy are the least frequent devices. The percentage of repetition decreases from 4th grade to 6th grade while in hyponymy and meronymy it is increased. According to Kruskal–Wallis test the differences of using synonymy and repetition are not significant although differences of using collocation, hyponymy and meronymy are significant (p≤ 0/05). It seems that not only the frequency of different lexical cohesive devices in students’ written discourse increases as the grades increase, but also more sophisticated lexical cohesive devices are found in writings of the students in higher grades. Keywords: Lexical cohesion, written discourse, Functional grammar, Students. M3 ER -