This document analyzes common errors made by students in written English and identifies contributing factors. It finds that the most common errors are issues with subject-verb agreement, spelling, and punctuation. Through teacher and learner interviews, it identifies several factors that contribute to these errors, including language interference from students' first language, overgeneralization of rules, a lack of practice/reading, low motivation, and the influence of texting language. Both teachers and learners agree that anxiety, lack of self-confidence, and ineffective teaching methods also impact students' written English abilities.