There are 84 units and 6 business files. Each unit consists of: 1. language presentation through: sample sentences to show the language forms in use; an explanation of the language forms; a description of the uses of these forms; 2. practice through: controlled exercises to develop recognition of the language forms; controlled exercises to practise combining language forms and language use; controlled or guided exercises focusing on language form and meaning; transfer actitives to practise transferring the language presented in the unit to the student's own personal and professional experience; 3. answers to the controlled and guided exercises.