The document defines and describes adjective phrases. It begins by explaining that an adjective phrase is a group of words that serves to describe a noun or pronoun, functioning like an adjective. It then provides tips for identifying adjective phrases based on the first word. Adjective phrases can be made of an intensifier and adjective or multiple adjectives. They can modify nouns or pronouns. The document also distinguishes adjective phrases from adjectival phrases and provides many examples of adjective phrases in sentences.