Comparatives are used when we compare two things or two people.
One-syllable adjectives.
For adjectives with one syllable, add –ER to the adjective.
Tall – taller
Two-syllable adjectives
Adjectives with three or more syllables
For adjectives with three syllables or more, add MORE or LESS to the adjective.
Exceptions

These adjectives can be used with –ER and MORE / LESS.
Clever – clever and more / less clever
Gentle – gentler and more / less gentle
Friendly – friendlier and more / less friendly
Simple – simpler and more / less simple [2]
Noun (subject) + verb + comparative adjective + than + noun (object).
Examples of comparatives
“Timbertwig rushed out of doors and climbed up on to the roof of the house. He always went there when he was sad, and he had never been sadder than today.” [3, p.192]
“Then she noticed Timbertwig’s hat. “Oh where did you get that? It’s scruffier than the last one! What’s inside it?” [3, p. 196]
“As he grew older, the boy’s face turned a deep golden colour, brighter than the shine of his little golden bow. And when he sat on the beach, gazing out to sea, the weather was always calm and there were strange bright lights on the water.” [4, p.82]
“Paddington did look much cleaner than when he had first arrived at the Browns. His fur, which was really quite light in colour and not dark brown as it had been, was standing out like a new brush, except that it was soft and silky. His nose gleamed and his ears had lost all traces of the jam and cream. He was so much cleaner that when he arrived downstairs and entered the dining-room some time later, everyone pretended not to recognise him.” [5, p.34-35]
Song: Life is getting more and more complicated. [6]
Sources:
- Languagelearningbase.com. (2018). Irregular Adjectives in Comparatives and Superlatives – learn English,grammar,adjectives,english. [online] Available at: http://languagelearningbase.com/86198/irregular-adjectives-in-comparatives-and-superlatives [Accessed 7 Oct. 2018].
- EFLnet. (2018). Forming Comparative and Superlative Adjectives. [online] Available at: http://www.eflnet.com/tutorials/adjcompsup.php [Accessed 8 Oct. 2018].
- Story Teller Part 7. (1983). Marshall Cavendish Limited, pp.192-196.
- Story Teller Part 3. (1983). Marshall Cavendish Limited, pp.81-85.
- Bond, M. (1992). A Bear Called Paddington. HarperCollinsPublishers.
- Graham, C. (1993). Grammarchants. More Jazz Chants. Oxford University Press, p.69.