The Different between A, An and The

The Different between A, An and The.very simply:
* A and An just mean one of a class.
* The means 'you know exactly which one.'

Compare :

* A doctor must live people.
(= any doctor, any one of that profession)
* My brother's a doctor
(= one of that profession)
* I am going to see the doctor.
(= you know which one: my doctor)
* I live in a small flat at the top f an old house near the town hall.
(=a small flat : there must be two or three. At the top of the house - it could be any one of these. an old house : there are lots near the town hall - it could be anyone. The top : we know exactly which town hall is meant: there's only one in the town.)

Article with uncountable nouns

Click here to know Special rules and exceptions.