Language in Use．Beginner：Self-study Workbook Language in Use．Intermediate：Self-study workbook Language in Use．Upper-intermediate：Self-study workbook Language in Use．Pre-Intermediate：Self-study Workbook Language in Use．Beginner：Self-study Workbook with Answer Key Language in Use．Beginner：Classroom Book Language in Use．Beginner：Teacher's Book Language in Use．Upper-intermediate：Self-study workbook with answer key Language in Use．Intermediate：Self-study Workbook with Answer Key Language in Use．Pre-Intermediate：Self-study Workbook with Answer Key