Why is sheep a countable noun?
Nouns that refer to objects that we can count as individual items are called countable nouns. Sheep can be counted - 'one sheep, two sheep, three sheep' (note that the singular and plural are the same for sheep.) An example of something that we cannot count in this way is water. Water is an uncountable noun. We cannot say 'one water, two waters, three waters etc.' we need to use a measure such as a 'litre'.
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