Main points

* You use `Could you’ to tell someone politely to do something.

* Imperatives are not very polite.

* You also use `Could you’ to ask someone politely for help.

* You use `I would like’, `Would you mind’, `Do you think you could’, and `I wonder if you could’ to make requests.

1 When you want to tell someone to do something, you can use `Could you’, `Will you’, and `Would you’. `Could you’ is very polite.
Could you make out her bill, please?
Could you just switch on the light behind you?

`Will you’ and `Would you’ are normally used by people in authority. `Would you’ is more polite than `Will you’.
Would you tell her that Adrian phoned?
Will you please leave the room?

Note that although these sentences look like questions (`Will you’, not `You will’), they are not really questions.

2 If someone in authority wants to tell someone to do something, they sometimes say `I would like you to do this’ or `I’d like you to do this’.
Penelope, I would like you to get us the files.
I’d like you to finish this work by Thursday.

3 You can use an imperative to tell someone to do something, but this is not very polite.
Stop her.
Go away, all of you.

However, imperatives are commonly used when talking to people you know very well.
Come here, love.
Sit down and let me get you a drink.

You often use imperatives in situations of danger or urgency.
Look out! There’s a car coming.
Put it away before Mum sees you.

4 When you want to ask someone to help you, you use `Could you’, `Would you’, `Can you’, or `Will you’. `Could you’ and `Would you’ are used in formal situations, or when you want to be very polite, for example because you are asking for something that requires a lot of effort. `Could you’ is more polite than `Would you’.
Could you show me how to do this?
Would you do me a favour?

`Will you’ and `Can you’ are used in informal situations, especially when you are not asking for something that requires a lot of effort.
Will you post this for me on your way to work?
Can you make me a copy of that?

5 You also use `I would like’ or `I’d like’, followed by a `to’-infinitive or a noun group, to make a request.
I would like to ask you one question.
I’d like steak and chips, please.

6 You can also make a request by using:

* `Would you mind’, followed by an `-ing’ form
Would you mind doing the washing up?
Would you mind waiting a moment?

* `Do you think you could’, followed by the base form of a verb
Do you think you could help me?

* `I wonder if you could’, followed by the base form of a verb
I wonder if you could look after my cat for me while I’m away?