words which take the --er and --est endings to show comparative are adjectives (or adverbs) adjectives ending in "---ing" are the participial adjectives (formed from verbs: like annoying, exasperating, frightening, gratifying, misleading, thrilling, time-consuming, worrying) I would always intensify these by using more /most - NEVER by adding ---er or ---st to the adjective. htm
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