We use the when there is only one of something:
- Have you ever crossed the equator? (there is only one equator)
- What's the Longest river in Europe?
- Our apartment is on the tenth floor.
- Buenos Aires is the capital of Argentina.
- I'm going away at the end of this month.
We use
the before
same (
the same):
- Your sweater is the same colour as mine. (not is same colour)
- 'Are these keys the same?' 'No, they're different.'
We say:
- the sun
- the moon
- the earth
- the world
- the universe
- the sky
- the sea
- the ground
- the environment
- the internet
- I love to look at the stars in the sky. (not in sky)
- The internet has changed the way we live.
- We need to do more to protect the environment. (= the natural world around us)
- The earth goes round the sun, and the moon goes round the earth.
We also use '
Earth' (without
the) when we think of it as a planet in space (like
Mars,
Jupiter etc.).
- Which planet is nearest Earth?
We say
space (without
the) when we mean 'space in the universe'. Compare
- There are millions of stars in space. (not in the space)
- I tried to park my car, but the space was too small.
We use
a/
an to say what kind of thing something is (see Unit 71 B). Compare
the and
a:
- The sun is a star. (= one of many stars)
- The hotel we stayed at was a very nice hotel.
We say: (go to)
the cinema,
the theatre.
- I go to the cinema a lot, but I haven't been to the theatre for ages.
When we say the cinema / the theatre, we do not necessarily mean a specific cinema or theatre.
We usually say
the radio, but
television/
TV (without
the). Compare:
- I listen to the radio a lot. but I watch television a lot.
- We heard it on the radio. but We watched it on TV.
The television /
the TV = the television set:
- Can you turn off the television, please?
We do
not use
the before
noun +
number. For example, we say:
- Our train leaves from Platform 5. (not the Platform 5)
- (in a shop) Do you have these shoes in size 43? (not the size 43)
In the same way, we say: Room 126 (in a hotel), page 29 (of a book), question 3 (in an exam), Gate 10 (at an airport) etc.