An Analysis of Grammatical Errors in English Writing of Thai University Students


  • Preeyanuch Promsupa
  • Patchara Varasarin
  • Prapart Brudhiprabha


English Writing, Error Analysis, Grammatical Errors, Interlanguage Errors, Intralingual and Developmental Errors


           The purposes of this study were to investigate grammatical error types and analyze sources of the errors in English writing. The collected data were from 34 English essays written by 34 Thai second year English majors in one university in Thailand. The data were analyzed based on the framework of grammatical error classification to find the error types, frequencies, percentages, and ranks. Furthermore, plausible causes of the errors were explained by counting on the two error sources: 1) interlanguage errors and 2) intralingual and developmental errors. The research findings revealed that 2,218 grammatical errors were found in both of two main types: morphological errors (81.97%) and syntactic errors (18.03%). Of all two main types, there were 32 error sub-types. The three most frequently found errors were singular/plural errors (30.43%), article errors (21.51%), and preposition errors (5.23%) respectively. In regards to the sources of the errors, both of the interlanguage errors and the intralingual and developmental errors had influences on the errors made in the writing. The interlanguage errors occurred when the students attempted to use their existing knowledge of L1 structures to acquire the target language, but differences between the two languages caused them to apply the structures incorrectly. The intralingual and developmental errors were found because of difficulties and problems within the target language itself. The findings were beneficial for learning and teaching of English writing. They could enable the students to be aware of common grammatical error commission while writing English. In addition, the students might get more understanding of influential sources of errors made. Moreover, the teachers and the syllabus designers could use the results as guidance to design and develop more suitable teaching material and techniques.

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