Uncountable Nouns

[Emanuelli]

Hello:

Here I am again to ask you about the definition of Countable/Uncountable nouns that we see in dictionaries.

For example: Apple (C/U), but it doesn't mention when it's Count. or Uncountable.

Other example was with Pear (C/U).

Food (C/U)

How do I know? Can I use both of them?

Thank you.

Emanuélli

*PS: Two cups of coffee = two coffees???
Three bottles of beer = two beers???

[Casiopea]

Count: How many?
apple, apples
pear, pears

Non-Count: How much?
food, food

How many?
(foods *rare)

Two cups of coffee, two coffees (OK)
Three bottles of beer, two beers (OK)