The comparative form of an adjective or adverb compares two things. The comparative is formed by adding the suffix er to the modifier (for some short words) or by using the word more with the modifier:
The superlative form compares three or more things. The superlative is formed by adding the suffix est to the modifier (for some short words) or by using the word most with the modifier:
If you are not certain, consult a dictionary to see which words take more and most and which words take the suffixes er and est.
There are certain modifiers that cannot logically be used in the comparative and superlative forms. Adjectives like perfect and unique, for instance, express absolute conditions and do not allow for degrees of comparison. Something cannot be more perfect than another thing: it is either perfect or not perfect.
Avoid the double comparison—that is, using both a suffix and an adverb to indicate the comparative or superlative:
Similarly, avoid the double negative—the use of two negative words together to form a single negative idea. While the double negative is common in speech and has a long history in the English language, it should not be used in formal writing:
Double negatives involving not and no are fairly easy to spot and fix. However, some adverbs (for example, hardly, scarcely, barely) imply the negative and should not be used with another negative:
© Department of English, Faculty of Arts, University of Ottawa, 2013