1. The DEFINITE article
1.1. groups and classes
1.1.1. groups of people
1.1.1.1. national groups
1.1.1.1.1. The English like drinking tea.
1.1.1.2. age groups
1.1.1.2.1. The old have time to play cards.
1.1.1.3. social groups
1.1.1.3.1. The poor cannot even afford to buy a loaf of bread.
1.1.1.4. bands
1.1.1.4.1. My uncle was a great fan of the Rolling Stones.
1.1.2. animal classes
1.1.2.1. The lion [= lions] is threatened with extinction.
1.1.3. groups of objects
1.1.3.1. musical instruments
1.1.3.1.1. Mark has been playing the guitar ever since his childhood.
1.1.3.2. titles
1.1.3.2.1. newspapers
1.2. geographical names and places
1.2.1. countries in the plural / collective/
1.2.1.1. the UK, the Netherlands
1.2.2. compass points and areas
1.2.2.1. the North
1.2.3. rivers and oceans
1.2.3.1. the Thames, the North Atlantic Ocean
1.2.4. mountain ranges
1.2.4.1. the Pennines
1.2.5. post-modification with "of"
1.2.5.1. the university of Oxford = Oxford University [without article!]
2. The INDEFINITE article
2.1. jobs
2.1.1. Tony is a doctor.
2.2. measuring
2.2.1. She used to visit us three times a week.
2.3. unknown people
2.3.1. A certain Mr Jones called while you were out.
2.4. a famous work of art
2.4.1. He bought a Van Gogh the other day.
3. The ZERO article
3.1. names
3.1.1. Matthew was a student of mine.
3.2. streets
3.2.1. Yellow Road
3.3. sports
3.3.1. We were playing basketball.