This ESL worksheet is tailored for adults and teenagers to master defining relative clauses with clear explanations, practical exercises, and creative writing tasks. Students will learn to confidently use relative pronouns like "who," "which," "where," and "when" in various sentence structures. With fill-in-the-blank questions, error correction, sentence rewrites, and personalized definitions, this worksheet is perfect for B1-B2 learners to strengthen their grammar skills and enhance fluency.