one and ones, questions

one and ones

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?

questions

 

Which question word to use?

We use who to ask questions about people:

Who is that?
Who lives here?
Who did you see?

We use whose to ask about possession:

Whose coat is this? [or] Whose is this coat?
Whose book is that? [or] Whose is that book?
Whose bags are those? [or] Whose are those bags?

We use what to ask questions about things:

What is that?
What do you want?

We use which to ask someone to choose something:

Which came first, the chicken or the egg?
I’ve got two books. Which do you want?

We can also use what and which with nouns:

What subjects did you study at school?
What newspaper do you read?
Which newspaper do you read – the Times or the Guardian?
Which book do you want?
Which one is yours?

Questions with prepositions:

Questions ending in prepositions are very common in English. After Who, Which or What we often have a preposition at the end of the sentence:

Who does this book belong to?
What are you looking for?
Which university did you go to?
What country do you come from?