Interchange Fourth Edition is a four-level series for adult and young-adult learners of English from the beginning to the high-intermediate level. Workbook A, Intro has six-page units that follow the same sequence as Student´s Book A, Intro. The workbook helps recycle and review language by providing additional practice in grammar, vocabulary, reading, and writing. It contains units 1-8 and is appropriate for in-class work or assigned as homework.