Do you know how to use one or ones?

As a determiner, the word one is sometimes used before a proper noun to designate, particularly, this person: ''He delivered the package to one Ronald Pepin of Colchester.'' The article ''a'' will also function in that position for the same purpose.
Sometimes we use the word one as an adjective, as in ''I'll have just one scoop of ice-cream,''

Sometimes the pronoun one functions as a numerical expression:

look at the ice cream. I think I'll have one.
One is red, the other blue.
One is hardly enough.
They love one another
The other one will win the competition.

As a pronoun, one can also function in an impersonal
One would think not to do that.
if one fails, then we must try another.
In the numerical sense.

We watched as one (victims) was pulled out of the car.
However, it is generally regarded as a bad idea to mix the impersonal or generic pronoun one with another pronoun, especially in the same sentence, as in ''If one fails, then he/you must simply try harder.''

Plural of One

I really like the red ones.
The ones with metal handles are nicer.
Do you want these ones? (pointing at the object)

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