We have teacher manuals and downloadable supplements available for many of our textbook series, but they are available only to teachers using the textbook in a course. To protect the integrity of the teacher materials we cannot provide answer keys or other supplemental teacher materials to students or independent learners. Teachers, please contact us with your name, school/institution you are associated with, and the name of your course. If you are unable to use a school e-mail address (i.e. firstname.lastname@example.org), please provide a phone number or another method of contact.