This lesson shows you the different ways to use this word. There is also a plural pronoun, ones.
One of my brothers has just gone to England.
Can I have one of your cigarettes?
There is only one way to learn English; you have to practice.
I said one cup of coffee, not two.
I tried on three dresses. The nicest one was very expensive.
There are four cars here. Which one is yours?
Mine is the one on the right.
I don't usually like bananas, but these ones are delicious.
We have some good players, but the best ones always go and play in other countries.
He was going to make a chicken sandwich, so I asked him to make one for me, too.
People tell me I should get a car but I don't want one.
NOTICE: one is seldom used as a subject pronoun for people.