The superlative is the form of an adjective or adverb that expresses the highest or a very high degree of the quality of what is being described. For example, if you are describing a noun, in the sentence:
“Everest is the highest mountain in the world”
the word highest is a superlative adjective. If you are describing a verb, use a superlative adverb, e.g.
“Of all the runners, Cathy Freeman ran the fastest.”
The word fastest is a superlative adverb.
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