We use one (singular) and ones (plural) to avoid unnecessary repetition.

See those two girls? Helen is the tall one and Jane is the short one.
Which is your car, the red one or the blue one?
My trousers are torn. I need some new ones.
See those two girls? Helen is the one on the left.
Let’s look at the photographs. The ones you took in Paris.

We often use them after Which ... in questions:

You can borrow a book. Which one do you want?
There are lots of books here. Which ones are yours?




Hi Echo,

Grammatically, one is active and one is passive, but there is no difference in meaning or use.

Best wishes,


The LearnEnglish Team

I need to know which is the correct choice;.
Which socks do you wear? The black ( one / ones ) .

Thank u

Hello Kaz,

'sock' is the singular form and 'socks' is a plural form. Likewise, 'one' is a singular form and 'ones' is plural. The two should match.

I hope this helps you find the correct answer.

Best wishes,
The LearnEnglish Team

Please help me with this question. I have 2 sentences:
1/ Who goes to school with you?
2/ Who go to school with you?
I was told that I must always use singular verb in "who" and "what" questions. Anyway, is the second sentence always incorrect?

Hello hungduc,

It is not incorrect to use a plural verb with 'who'. However, if we do not know that the answer is going to be plural then we generally use a singular verb. For example:

'Who goes to school with you?' - a general question

'Who go to school with you?' - a question I might ask when looking at a group of people and asking which of them go to school with you

I hope that helps to clarify it for you.

Best wishes,


The LearnEnglish Team

Thank you very much, Peter. I really appreciate your help.

Actually reding comment of the lesson add more informaition to my knowledge .
Thanks all

Thanks a lot

thanks you!!! :D

pls help me with this sentence. He is one of the authors who is respected. (Should 'are' come in place of 'is') .What is the rule to deal with these type of sentences. Also what should come in - One of the authors who is respected is ABC. (is/are) ??
Pls guide me.