Morphologically, most adjectives are gradable. That is, they express the grammatical category known as degree. The basic form of the adjective, which expresses a quality, is known as the positive degree. To express a greater intensity of one of two items, the comparative degree is used, either by adding the suffix –er or with the word more and the basic adjective. To express the greatest intensity among three or more items, the superlative degree is used, either with –est or most.
Adjectives typically specify characteristics of nouns, or they limit the application, as in "the large refund," "an enthusiastic participant," or "purple prose." Most often they appear before a noun, although they can also appear in their own phrases after certain verbs known as linking verbs, as in "Wilma looks cheerful." or "They were happy."
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