The Words You Often Mix Up is a practical textbook designed for first-year students of non-linguistic universities. The manual focuses on eliminating common lexical errors caused by phonetic, structural, and semantic similarities between English words. Based on extensive experimental research and analysis of diagnostic tests, the book organizes frequently confused vocabulary into structured word groups. Each group includes transcription, translation, illustrative examples, and contextual exercises, followed by control tests and answer keys for self-assessment. The textbook aims to improve students' vocabulary accuracy, develop correct semantization skills, and strengthen speaking and reading competence. It serves as an effective supplementary tool for mastering English lexical distinctions.