Form and rules
How it works
Use a/an with one singular countable noun when it is not yet specific: I need a taxi.
Use the when the speaker and listener know which person or thing is meant, or when it has already been mentioned.
Use the with unique or clearly identified things in a situation: Close the door. The sun is hot.
Use no article for plural or uncountable nouns when speaking generally: I like dogs. Music helps me relax.
Do not use a/an with plural or uncountable nouns: not a water, not a books.