1/ The comparative: Preposition THAN is used to make comparison between two things/people.
- One syllable adjectives (e.g: young, old, rich etc.):
Subject + am/is/are + ADJECTIVE + ER + THAN + object
Ex: He is my brother. He is 2 years younger than me.
They are richer than our neighbours.
- Two or more syllable adjectives:(e.g: narrow, beautiful, handsome etc.):
Subject + am/is/are + MORE + adjective + THAN + object
Ex: John is more handsome than Neil.
- BUT: good = BETTER THAN ; bad = WORSE THAN
Ex: His English is much better than mine.
My mother's health has become worse recently.
2/ The superlative: The article THE is put before the superlative adjectives and we add EST after the one syllable adjectives (e.g: the eldest; oldest; newest etc.) and MOST before the two or more syllable ones (e.g: the most handsome; the most beautiful etc.) BUT the best; the worst.
Ex: She is the youngest sister in the family.
Diana is the most beautiful girl in the party.
B/ We use ELDER or OLDER to talk about the members of the family.
Ex: He is my elder/older brother. He is 3 years older (NOT elder) than me.