RULES TO FORM THE COMPARATIVE AND THE SUPERLATIVE

1º In English, most of the adjectives are added an ‘er’ at the end to form the comparative and ‘est’ to form the superlative.

Adjetives	Comparative	Superlative
Long	Longer	Longest
Short	shorter	shortest
Old	older	oldest
High	higher	highest

2º If the adjective ends in ‘e’, only one ‘r’ is added for the comparative and ‘st’ for the superlative

Adjetives	Comparative	Superlative
Nice	Nicer	Nicest
Late	Later	Latest
Rare	Rarer	Rarest

3º Some adjectives that end in consonant, duplicate the final consonant to form the comparative and the superlative, like this:

Adjetives	Comparative	Superlative
Fat	fatter	Fattest
Thin	Thinner	Thinnest
Hot	Hotter	Hottest
Big	Bigger	Biggest

4º When the adjective ends in ‘and’, the ‘and’ is changed to a ‘i’ and added at the end ‘er’ to form the comparative and ‘est’ to form the superlative, as follows:

Adjetives	Comparative	Superlative
Sunny	Sunnier	Sunniest
Funny	Funnier	Funniest
Tasty	Tastier	Tastiest
Happy	Happier	Happiest

5º Some adjectives, however, do not have a different form for the comparative or the superlative, and ‘more’ and ‘most’ must be used to form them. They are generally adjectives that have more than two syllables or end in ‘ful’, ‘ing’, ‘ous’, ‘ive’, ‘ish’, ‘al’, ‘able’ and ‘ed’.

Adjetives	Comparative	Superlative
Beautiful	More beautiful	Most beautiful
Careful	More careful	Most careful
Boring	More boring	Most boring
Delicious	More delicious	Most delicious

6º There are three very common English adjectives that are irregular. They have completely different comparatives and superlatives; these are:

Adjetives	Comparative	Superlative
Good	Better	Best
Bad	Worse	Worst
A lot	More	Most