5. Discussion
As stated earlier, a good revision is needed during the writing process in order to make a paragraph or an essay
more accurate. The knowledge regarding the differences between L1 and L2 linguistic properties is thus
perceived as essential. Ferris (2004), a well-known researcher in the area of error feedback in L2 writing, states
that prior to giving feedback to students, it is crucial for a writing teacher to be aware of error categories
frequently found in his/her students’ writing. For this reason, over the last few decades, many language
researchers have paid attention to writing error detection, resulting from the interference of the first language.
Maros et al. (2007) investigated grammatical errors made by Malaysian students. The findings showed that their
errors caused by L1 interference were the use of articles, subject-verb agreement, and copula ‘be’. As can be
seen, both Malaysian and Thai students had similar L1 interference categories, which were the use of articles and
subject-verb agreement. Besides, Abushihub et al. (2011) categorized grammatical errors in students’ writing into
six major categories: tenses, prepositions, articles, active and passive voice, verbs, and morphological errors. The
two most frequently made error types were prepositions and morphological errors related to the use of words and
word forms. Compared to Thai students, L1 interference that caused ineffective writing were relatively similar to