|We use the definite article the|
|1. to refer to something or someone both speakers in a conversation know about:
I've got two children – a boy and a girl. The boy is 7 and the girl is 4.
2. before seas, rivers, and groups of mountains or islands:
3. if there is only one of these people or things:
the King the UN the sun the White House
4. with superlatives:
the tallest the fastest the most expensive the best