1) -est at the end of the adj if the adj has 1 syllable.
Ex: old =>the oldest
nice => the nicest
2) -est to the adj that has 2 syllables and end in -y . Change the y to i.
Ex: lazy =>the laziest
busy => the busiest
3) -est to adj that end in consonant-vowel-consonant and double the last consonant.
Ex: hot =>the hottest
fat =>the fattest
sad =>the saddest
4) most to the adj that has 3 syllables or more but do not end in -y.
Ex: important =>the most important
expensive =>the most expensive
