One / ones
Avoiding repetition
1. One and ones
One is a pronoun used to replace a singular countable noun, so as to avoid unnecessary repetition.

- I've bought these two lipsticks.

- I like both but the purple one is gorgeous.
However, we will use ones to replace plural countable nouns.

- Whose are these socks?

- The big ones are mine.
2. How are one and ones used?
These particles are used according to specific structures:
WHICH ONE

Which one do you want? (apple)
WHICH ONES

Which ones do you want? (apples)
THIS / THAT ONE

This one is blue and that one is red. (teddy bear)
THESE / THOSE ONES

These ones are blue and those ones are red. (teddy bears)
THE ONE

The one on the left is more expensive. (dress)
THE ONES

The ones on the right are more expensive. (shoes)
THE + ADJECTIVE + ONE

The big one is a Dane and the small one is a Puli. (dog)
THE + ADJECTIVE + ONES

Which gloves do you like best, the white ones or the red ones?
A/AN + ADJECTIVE + ONE

His car is very old. He needs a new one.
SOME + ADJECTIVE + ONES

If you want tomatoes, I have some very good ones.
Remember!
The pronoun one is used to replace a singular countable noun. However, we use the pronoun ones when we replace plural countable nouns.
Singular | Plural |
---|---|
Which one? | Which ones? |
This / that one | These / those ones |
The one | The ones |
The + adjective + one | The + adjective + ones |
A/an + adjective + one | Some + adjective + ones |