argumentative writing, text structure, vocabulary, grammatical
features, EFL learners, qualitative content analysis, junior secondary school.
E. This study aims to analyze the linguistic features of students’ argumentative
writing in terms of text structure, vocabulary, and grammatical features, as
well as to examine how these dimensions interact in shaping overall writing
quality. The research employed a qualitative content analysis approach
grounded in the Genre-Based Approach, Systemic Functional Linguistics,
and Error Analysis Theory. The study was conducted at Kinderfield
Highfield School Depok and involved 40 Grade VIII students who produced
20 collaboratively written argumentative essays. Data were collected through
writing tasks, teacher interviews, and document analysis. The findings
revealed that all texts demonstrated a recognizable argumentative structure
consisting of an introduction, body, and conclusion. However, 30% of the
texts contained implicit or unclear thesis statements, while 90% exhibited
cohesion and coherence problems. In terms of vocabulary, 78 lexical errors
were identified, with word choice errors being the most frequent (52.6%),
followed by collocation errors (30.8%) and redundancy errors (16.7%).
Grammar was the most problematic linguistic aspect, with 100 grammatical
errors identified. Tense errors accounted for 43% of all grammatical errors,
followed by sentence structure errors (36%) and subject–verb agreement
errors (21%). The integrated analysis showed that weaknesses in text
structure, vocabulary, and grammar were closely interconnected. The
findings suggest the need for integrated writing instruction that develops
argument structure, vocabulary use, grammatical accuracy, and cohesion in
EFL argumentative writing.