Comparative adjectives are used to compare and describe two things and people. It also describes something or someone that/who changes. Furthermore, we use the comparative adjective to refer to one thing that depends on another thing.
Comparative adjective is formed with -er at the end. This is when the adjective consists of 1 or 2 syllables. When it consists of more syllables, it gets 'more' before the adjective.
When the adjective ends on 'y', it changes in 'i' and gets -er at the end.
We use 'than' to compare two things in a sentence.
'And' is put between two adjectives when we describe a change of someone or something.
'The' is used when something depends on something else.
There are also irregular forms of adjectives. Think of the following words: good, bad, little (amount), little (size), much (uncountable) and many (countable).