Use Retin-A exactly as your doctor has prescribed it for you. Follow all directions on your prescription label. Do not use this medicine in larger or smaller amounts or for longer than recommended. Do not take by mouth. Retin-A is for use only on the skin.
Definition of wall for English Language Learners : a structure of brick, stone, etc., that surrounds an area or separates one area from another : the structure that forms the side of a room or building
A word wall is a systematically organized collection of words displayed in large letters on a wall or other large display place in the classroom. It is a tool to use, not just display. Word walls are designed to promote group learning and be shared by a classroom of children.