Cengage Learning
Cengage Learning: Adjectives and Adverbs Comparative and Superlative Forms
This is an English style guide article focusing on comparative and superlative forms of adjectives and adverbs. It explains how to form these adjectives and adverbs, how to use them, and provides examples.
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Grammar: Adjectives and Adverbs [Pdf]
This document offers an explanation regarding the formation of adjective comparison and order in a sentence. PDF (requires Adobe Reader).