Plural and singular after the word "of"

[Phil100]

Hi,

I have never quite understood when to use either singular or plural after the word "of" e.g.

Staff with 200 yrs of experience.
Stuffs of nightmare
Illegal cockfight

Why the above not written as experiences, nightmares and cockfights?

Thank you in advance,
Phil

[Raymott]

Hi,

I have never quite understood when to use either singular or plural after the word "of" e.g.

Staff with 200 yrs of experience.
Stuffs of nightmare
Illegal cockfight

Why the above not written as experiences, nightmares and cockfights?

Thank you in advance,
Phil

Whether you use a singular or plural has absolutely nothing to do with the word "of".
If you have one illegal cockfight, that's singular. If you have two illegal cockfights, it's plural - though where's the "of" in that example?
"Stuffs of nightmare/s" is never used. The only possible phrase is "stuff of nightmares" - because it's the stuff nightmares are made of - nothing to do with "of".
With the first phrase, you're dealing with whether "experience" is countable or uncountable.

[Phil100]

[QUOTE=Raymott;

Thanks.