Formation of Comparative Adjectives

There are two ways to make or form a comparative adjective:

Short adjectives
1-syllable adjectives	old, fast
2-syllable adjectives ending in -y	happy, easy
Normal rule: add "-er"	old > older
Variation: if the adjective ends in -e, just add -r	late > later
Variation: if the adjective ends in consonant, vowel, consonant, double the last consonant	big > bigger
Variation: if the adjective ends in -y, change the y to i	happy > happier
Long adjectives
2-syllable adjectives not ending in -y	modern, pleasant
all adjectives of 3 or more syllables	expensive, intellectual
Normal rule: use "more"	modern > more modern expensive > more expensive

With some 2-syllable adjectives, we can use '-er' or 'more':

Exception
The following adjectives have irregular forms: