This document defines and provides examples of different types of adjectives in English: regular and irregular comparatives and superlatives, adjectives that use "more" and "most", and adjectives that cannot be comparative or superlative. It explains that regular adjectives form the comparative with "-er" and superlative with "-est", while some irregular adjectives completely change form. Adjectives with three or more syllables typically use "more" and "most". Certain adjectives like "perfect" cannot be compared at all.