Is sky a countable noun or an uncountable noun?
121562
When do we say "skies" instead of "sky"?
67915
Nouns that can be both count and noncount nouns
10054
When to treat 'Police' as a singular noun and a plural noun?
35049
What is the collective noun for a collection of collective nouns?
7374
Are collective nouns always plural, or are certain ones singular?
144463
Can a material noun be countable?
142144
Countable or uncountable; family of disjoint triangles?
108922
Cardinality and infinite sets: naturals, integers, rationals, bijections
19777
Defining "Countably Infinite"
18707
"The maximum number": plural or singular?
91872
Indefinite article before uncountable "drink" nouns, e.g. "a water"
136750
How to determine if a noun is a place or a thing
65604
Singular or plural form of property, when describing an object with N-count for the property
127022
"[adjective] and [adjective] [noun]" -- Should the noun be singular or plural?
156121
Existential-universal vs Universal-existential quantifiers
65920
Is "life" a countable noun in English?
117133
Is there an infinite countable $\sigma$-algebra on an uncountable set