This study aims to identify and classify syntactic errors made by EFL Saudi secondary students and the causes behind these errors through written form. The study includes 15 female students of the third secondary grade enrolled in Third Secondary School for Females in Al-Quway'iyah. The data were collected from a diagnostic writing test requiring the students to write a composition about one of three topics. The students' errors were classified into 15 different categories and analyzed using the Error Analysis Matrix. The findings show that most secondary students who were learning EFL made errors in syntax. Also, the study reveals that the students face complexity with different grammatical errors in terms of using punctuation, using articles, spelling, verbs, conjunctions, capitalization, fragments, lexicon, subject omission, pronouns, prepositions, using adjectives, and using nouns; that may hinder understanding the written text. Furthermore, the analysis of these errors reveal that interlingual interference and a lack of knowledge are the main causes of the students' errors.

This study aims to identify and classify syntactic errors made by EFL Saudi secondary students and the causes behind these errors through written form. The study includes 15 female students of the third secondary grade enrolled in Third Secondary School for Females in Al-Quway'iyah. The data were collected from a diagnostic writing test requiring the students to write a composition about one of three topics. The students' errors were classified into 15 different categories and analyzed using the Error Analysis Matrix. The findings show that most secondary students who were learning EFL made errors in syntax. Also, the study reveals that the students face complexity with different grammatical errors in terms of using punctuation, using articles, spelling, verbs, conjunctions, capitalization, fragments, lexicon, subject omission, pronouns, prepositions, using adjectives, and using nouns; that may hinder understanding the written text. Furthermore, the analysis of these errors reveal that interlingual interference and a lack of knowledge are the main causes of the students' errors.