Number of syllables Comparative  Superlative
one syllable + -er + -est
tall taller  tallest 
one syllable with the spelling consonant + single vowel + consonant: double the final consonant:
fat  fatter  fattest 
big  bigger  biggest 
sad  sadder  saddest 
big, bigger, biggest
Number of syllables Comparative  Superlative
two syllables + -er OR more + adj + -est OR most + adj
ending in: -y, -ly, -ow
ending in: -le, -er or -ure
these common adjectives - handsome, polite, pleasant, common, quiet
happy  happier/ more happy  happiest/ most happy 
yellow  yellower/ more yellow  yellowest/ most yellow 
simple  simpler/ more simple  simplest/ most simple 
tender  tenderer/ more tender  tenderest/ most tender 
If you are not sure, use MORE + OR MOST +
Note: Adjectives ending in '-y' like happy, pretty, busy, sunny, lucky etc:. replace the -y with -ier or -iest in the comparative and superlative form
busy  busier  busiest 
Number of syllables Comparative  Superlative
three syllables or more more + adj most + adj
important  more important  most important 
expensive more expensive  most expensive 


a. A cat is fast, a tiger is faster but a cheetah is the fastest
b. A car is heavy, a truck is heavier, but a train is the heaviest
c. A park bench is comfortable, a restaurant chair is more comfortable, but a sofa is the most comfortable

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