Nouns and Pronouns: One / Ones

one / ones replace a countable noun so you do not repeat it.

• I need a pen. Have you got one?
• Which jacket do you prefer? The blue one.
• These shoes are too small. I need larger ones.

After an indefinite article: a new one. After the + adjective: the cheapest one.

Do not use one for uncountables: I prefer this coffee, not this one coffee meaning “this coffee (the drink)”.

Do not confuse this with the number one: one apple, two apples.