A knowledge

[Haihao]

Hi,

Could you please shed some light on this?

He has a knowledge of French.

Knowledge here looks like a count noun. But,

He doesn't have much knowledge of French.

Are there any theoretical explanations?

Thank you!

[Mister Micawber]

No theoretical explanations beyond the fact that modified non-count nouns often turn countable.
_________________
Native English teacher at Mister Micawber's

[Haihao]

Thank you, MM, but why He doesn't have a knowledge of French. sounds funny?

[Mister Micawber]

Because we would use 'any' with the negation:

He has a knowledge of French.
He doesn't have any knowledge of French.
He has an idea.
He doesn't have any idea.
He has a coffee.
He doesn't have any coffee.
_________________
Native English teacher at Mister Micawber's

[Haihao]

I see. But if he has a little knowledge of Franch, then,

He has a knowledge of Franch to some extent.

In this case, a could stay as before, but any coundn't, and much has to show up with the negation.

I'd like to know this mystery involving a and her counterpart 0.