Substituting Nouns with One/Ones

The use of one/ones

We often use one/ones instead of repeating a countable noun.

  • Singular: one

Can you lend me a pen? Sorry, I haven’t got one

I would like a steak, a big one, please.

  • Plural: ones

Red apples taste better than green ones

I would like to try on some trousers, the ones there look good.