Grammar — Articles: The indefinite article – a/an
- We use a/an with a singular countable noun when the listener doesn’t know which particular thing is being referred to, or it doesn’t matter which one. This is because:
- it is one of many of the same class, e.g. a computer, an orange
- we mention a person or thing for the first time: I’ve read a really good book.
Grammar — Articles: The definite article – the
- We use the (with any noun) when it is known which particular item is being referred to. This is because the thing/person:
- was mentioned before: I’ve read a really good book.
- The book is about …
- is unique: The Earth revolves around the Sun.
- is defined specifically by the words that follow, e.g. a relative clause: I love the book that my brother gave to me a few years ago.
- is a proper name: I like the crime novels of Agatha Christie.
- We also use the with:
- superlatives: The longest river in Egypt is the Nile.
- comparatives (when identifying one of a pair): I have two cousins. The older (of the two) is my favourite.
- ordinal numbers: The first man to walk on the moon was Neil Armstrong.
- decades, centuries: in the 1970s; in the 21st century
- plural names for countries, groups of islands and mountain ranges: the Netherlands, the Philippines, the Alps
- seas, oceans, rivers, deserts and areas: the Baltic sea, the Pacific ocean, the Thames, the Atacama desert, the Highlands
- The is also used when we refer to a group of people by their surname: the Smiths, the Joneses
Grammar — Articles: No article
- We use no article with plural and uncountable nouns when we make general statements:
- Life was very hard and over one million people emigrated.
- We use no article with words like prison, hospital, school, college, etc. when we are talking about their purpose as an institution, e.g. I go to school every day.
- He’s gone to college and he’s living in another city now.
- We use no article when we are referring to abstract nouns, e.g. peace, justice, courage.
- We use no article when referring to lakes, single islands, individual mountains: Lake Ontario, Ibiza, Snowdon
- We use no article with most geographical names, continents, countries, cities and towns, states: Europe, Dubai, Glasgow, Arizona (exceptions: the USA, the UK, the United Arab Emirates, the Hague)
- We use no article when we are referring to a group, class or species in general: Blackbirds can be seen all year round.
- It is also possible to use the, but with the singular noun:
- The red-winged blackbird breeds in wetlands across North America.