The comparative form of adjectives is used for comparing two objects in a sentence. Let’s look at some examples:

  • Alexa is smarter than Mike.
  • Alexa is more intelligent than Mike.

In this example, why is it ‘smarter’, but not *’intelligenter’? It all depends on the number of syllables that the adjective has. 


In English, when you use an adjective that has one to two syllables, it takes the -er suffix. Here are some examples of adjectives with one syllable:

  • Tall-taller
  • Small-smaller
  • Smart-smarter
  • Cold-colder

The same rule applies for adjectives with two syllables which end in an unstressed -y, but note that the spelling changes from -y to -ier. 

  • Pretty-prettier*
  • Happy-happier*
  • Noisy-noisier*

Words with three syllables need to have the word ‘more’ in front of them in order to show a comparison.

  • Successful-more successful
  • Intelligent- more intelligent
  • Fashionable- more fashionable
  • Beautiful- more beautiful

Exceptions 

A lot of times in English, there is no one-rule-fits-all. There are some frequently used adjectives which have an irregular comparative form. These you will have to memorize.

  • Good-better
  • Bad-worse
  • Little-less
  • Much-fewer
  • Far-farther

One final note to remember is that many learners will use both rules and will say sentences like:

  • *He is more faster than me.

Remember that an adjective either takes the -er suffix, or needs ‘more’ to be added in front of it in the comparative form. An adjective never takes both forms in the same sentence.