A Survey of the Cohesive Ties - Reference and Lexical Cohesion- in History Books of the Second and Third Grades in Guidance School in Iran

Halliday and Hassan believe that cohesion is one of the most important characteristics of a text and using cohesive ties –reference and lexical cohesion – make a text easy to understand. Providing school books that are easy to understand has always been the primary concern of education. The purpose of the present study was to investigate whether using cohesive ties in history books of the grades 2 and 3 in guidance school in Iran-Tehran make it easier to understand or not. The corpus of the study was about 10000 words from the second and third grade in guidance school. Odd lessons of every book were selected systematically so 5000 words of every book were analyzed according to Halliday and Hassan's pattern. After investigating the frequency of cohesive ties in texts through SPSS, K2 test was used to analyze whether the relationship between decreasing the number of cohesive ties and increasing the difficulty of a text is meaningful. The results of the study revealed that the lexical cohesion of the second grade had more cohesive ties than history book of the third grade and this change was meaningful. It is recommended that the authors specially the authors of school books utilize linguistic ideas and findings in writing the texts to make them more understandable for students.