an extra two days

[Julek15]

Hello ,

This is not my first post. I have been a member for a lot of years , however, something went haywire and I could not log in using my details I normally used.

I came across a piece of information saying that such phrases are correct.

an extra two days, a good many nights , a busy three days etc.

I don’t really know how to interpret it . I am familiar with “many a time” etc . but I have never come across the phrases I am asking about.


Is there a specific name for this grammatical phenomena ?


Thank you.

 

[RM1(SS)]

Is there a specific name for this grammatical phenomena ? phenomenon?

Not that I've ever heard.

 

[Edinburgher]

an extra two days, a good many nights , a busy three days etc.

It's an interesting construction, because as soon as you remove the adjectives extra/good/busy, the expressions become incorrect.
In the first and last example, you could think of it as omission of "period of": an extra period of two days, a busy period of three days.
The middle example is more complicated to explain, other than by treating "a good many" as a sort of fixed idiom.