"Could do with" - what is it?

[MartinEnglish]

Here's a question for fellow teachers - I like teaching "could do with" as it's such a common phrase yet I can't recall ever coming across it in any course or grammar books.

But what is it? Is it a model verb? It follows the same form (e.g. the past being "could have done with") Is it a phrasal verb? I can't even find it in the grammar books I have to hand.

I'd like to hear people's ideas.

Thanks

[5jj]

It's an idiomatic expression composed of the modal 'could' plus the prasal verb 'do with'. One of the oddities of 'do with' in that sense is that it is used only in combination with 'could' and, possibly, 'can'

[death]

it's an informal idiom. used to say that, you need or would like to have sth.
i could do with a drink.
her hair could have done with a wash.

[Tdol]

It's a minnow alongside make do with.

[MartinEnglish]

it's an informal idiom. used to say that, you need or would like to have sth.
i could do with a drink.
her hair could have done with a wash.

Yes, I know what it means thanks! I was asking what, grammatically, the structure is!

[MartinEnglish]

It's a minnow alongside make do with.

Yes, that's interesting, I hadn't thought of that one. But in what way is it a minnow?

[emsr2d2]

It's an informal idiom (no comma required) used to say that (no comma required) you need or would like to have sth something.
I could do with a drink.
Her hair could have done with a wash.

Hi death. Yes, it's me again. I will be writing this on all your posts until you start to do what we ask - start every new sentence with a capital letter.

[Tdol]

Yes, that's interesting, I hadn't thought of that one. But in what way is it a minnow?

It is a tricky thing to analyse, but make do with is . It's harder to categorise. Could do with can be explained as a phrasal verb that takes a specific modal verb, but....

[5jj]

Yes, I know what it means thanks! I was asking what, grammatically, the structure is!

We've told you - it's an informal, idiomatic expression. There is little point in trying to fit it into some grammatical category.