Grammar rule 1
When you have a single, countable English noun, you must always have an article before it. We cannot say "please pass me pen", we must say "please pass me the pen" or "please pass me a pen" or "please pass me your pen".Nouns in English can also be uncountable. Uncountable nouns can be concepts, such as 'life', 'happiness' and so on, or materials and substances, such as 'coffee', or 'wood'.
Grammar rule 2
Uncountable nouns don't use 'a' or 'an'. This is because you can't count them. For example, advice is an uncountable noun. You can't say "he gave me an advice", but you can say "he gave me some advice", or "he gave me a piece of advice".Some nouns can be both countable and uncountable. For example, we say "coffee" meaning the product, but we say "a coffee" when asking for one cup of coffee.
Grammar rule 3
You can use 'the' to make general things specific. You can use 'the' with any type of noun – plural or singular, countable or uncountable."Please pass me a pen" – any pen.
"Please pass me the pen" – the one that we can both see.
"Children grow up quickly" – children in general.
"The children I know grow up quickly" – not all children, just the ones I know.
"Poetry can be beautiful"- poetry in general.
"The poetry of Hopkins is beautiful" – I'm only talking about the poetry Hopkins wrote.
More uses of articles in English
Rivers, mountain ranges, seas, oceans and geographic areas all use 'the'.For example, "The Thames", "The Alps", "The Atlantic Ocean", "The Middle East".
Unique things have 'the'.
For example, "the sun", "the moon".
Some institutional buildings don't have an article if you visit them for the reason these buildings exist. But if you go to the building for another reason, you must use 'the'.
"Her husband is in prison." (He's a prisoner.)
"She goes to the prison to see him once a month."
"My son is in school." (He's a student.)
"I'm going to the school to see the head master."
"She's in hospital at the moment." (She's ill.)
"Her husband goes to the hospital to see her every afternoon."
Musical instruments use 'the'.
"She plays the piano."
Sports don't have an article.
"He plays football."
Illnesses don't have an article.
"He's got appendicitis."
But we say "a cold" and "a headache".
Jobs use 'a'.
"I'm a teacher."
Countries
We don't use 'a' if the country is singular. "He lives in England." But if the country's name has a "plural" meaning, we use 'the'. "The People's Republic of China", "The Netherlands", "The United States of America".Continents, towns and streets don't have an article.
"Africa", "New York", "Church Street".
Theatres, cinemas and hotels have 'the'.
"The Odeon", "The Almeira", "The Hilton".
Abbreviations use 'the'.
"the UN", "the USA", "the IMF".
We use 'the' before classes of people.
"the rich", "the poor", "the British".
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This source is from http://www.english-at-home.com/grammar/articles/
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Other Source
Form and meaning
- We use a / an when we are talking about something for the first time.
- He is wearing a suit and a tie.
- They have a cat.
- We use the when we are talking about a specific person or thing, or if there is only one, or if it is clear which one we are talking about.
- She took a glass of water and started to drink. (one of many glasses of water)
- She took the glass of water nearest to her. (a specific glass)
- She took the glass of water and started to drink. (there is only one glass of water)
- Can you turn on the TV? (it's clear we are talking about the TV in this room)
- I have to see the doctor tomorrow. (it's clear I am talking about my usual doctor)
- I need to see a doctor. (not any specific doctor)
- How many people have walked on the moon? (there is only one moon)
- The best film I've ever seen is Top Gun. (there can only be one best film)
- We use no article when we are talking about people or things in general.
- Carrots are good for you. (carrots in general)
- The carrots growing in my garden are almost ready to eat. (specific carrots)
- English people drink a lot of tea. (English people in general)
- The English people in this hotel are very nice. (specific English people)
- We use a / an to say what kind of person or thing someone or something is (often with an adjective, or to say it belongs to a particular group.
- You have a nice house.
- That's a very expensive car!
- A cat is an animal a bus is a vehicle.
- With school, university, prison, hospital, church, bed, work and home we use the when we are talking about a particular one, and no article when we are talking about the idea of school, university...
- The church on our street was built in the 17th Century. (a particular church)
- I go to church every Sunday (the idea of church, not a particular building)
- My friend works at the prison outside the city centre.
- My husband is in prison.
- The work isn't finished yet.
- I was feeling sick yesterday so I didn't go to work.
- The new bed is bigger than the old one.
- I put my children to bed a 8pm.
- We use the with singular countable nouns to talk about a type of thing.
- The computer was invented in the 20th Century. (not a particular computer)
- The computer in my office is broken. (a particular one)
- The crocodile is very dangerous. (this type of animal)
- The crocodile in the river is very big. (a particular one)
- She plays the piano. (not a particular piano but this type of instrument)
- The piano she is playing is very old. (a particular one)
- We use the + adjective to talk about a group of people (including nationalities).
- I always give money to the homeless.
- The unemployed receive money from the government.
- The French produce good wine.
- We use a / an to talk about someone's job.
- My wife is an optician.
- She works as a mechanic.
- We use no article with continents, countries, regions, cities, streets, mountains, lakes and parks.
- Asia, Italy, California, Bristol, Main St., Mount Everest, Lake Superior, Central Park
- We use the if the country contains Kingdom, Republic, State, Union
- The United Kingdom
- We use the with plural names of people and places.
- The Smiths, The Netherlands, The United States, TheBahamas, The Alps (also The Caribbean)
- We use the with oceans, seas, rivers and canals.
- The Atlantic Ocean, The Red Sea, The Nile, ThePanama Canal
- We use the with north, south, east and west to talk about the location of a place within another place, but no article to compare the location of two places.
- Greece is in the south of Europe.
- Spain is south of France.
- We use no article with northern, southern, eastern and western:
- Greece is in southern Europe.
- We normally use the with buildings, except if the first word is the name of a place.
- The White House, The Sheraton Hotel.
- Oxford University, Buckingham Palace.
This source is from http://www.eslbase.com/grammar/
