The lesson explains the rules for forming comparative and superlative adjectives.
Comparatives are used to compare two things. For one-syllable adjectives, we add -er (e.g., taller). If the adjective ends in -y, we change it to -ier (e.g., happier). For adjectives ending with a consonant + vowel + consonant, we double the last consonant and add -er (e.g., bigger). For adjectives with two or more syllables, we add more before the adjective (e.g., more beautiful). Some adjectives are irregular, such as good → better, bad → worse, and far → farther.
Superlatives are used to compare one thing with a group. For one-syllable adjectives, we add -est (e.g., tallest). If the adjective ends in -y, we change it to -iest (e.g., funniest). For two or more syllables, we add the most before the adjective (e.g., the most dangerous). Irregular forms include good → the best and bad → the worst.