How do we compare adjectives in English?

We use comparative to compare things. For this, we use two structures, although the formation of comparatives depends basically on the number of syllables in the adjective.  

      1. As + adjective + as
      2. Adjective + than

In this post, we will revise these two structures and we will also learn how the number of syllables influences the formation of comparatives. Let’s see these two structures separately: 

       1. As…as: 

When comparing with as… as, the adjective that we use in the middle does not change. That is to say, we do not add anything and we do not have to take into account the number of syllables making this form of comparison the easiest one.

Examples:

         She's twice as old as her sister.

         He's not as stupid as he looks!

       2. Adjective + than

When comparing with than, some changes are necessary, depending on the number of syllables of the adjective.

         A. One syllable adjectives: we add –er to the adjective

             My sister is much taller than me.

             It's colder today than it was yesterday.

Note: If the word ends: consonant-vowel-consonant, then the last consonant is usually doubled in the comparative. Examples: big-bigger, fat-fatter, hot-hotter.

       B. Two syllable adjectives ending in -y: we change the -y to –i and then we add -er

            She's looking happier today. 

         This grammar topic is easier than the last one.

   C. Other two syllable adjectives and adjectives with three or more syllables: we use more with the unchanged adjective

          The shops are always more crowded just before Christmas. 

       Is there anything more boring than reading about grammar? 

Finally, we also have to take into account that there are three forms that are irregular. In the following table you have them summarized:

Adjective Comparative good better bad worse far further / farther