I have three exams on my birthday. These are known as “countable” nouns. But some nouns are “uncountable”. These are things that are a concept, or not easy to divide. In general ...

Any with singular countable nouns However, when we want to emphasise that any means of any kind, it is quite natural to use any with singular uncountable nouns. So in your example, Esther ...

They play the piano. Countable nouns are objects that can be counted, such as brother or cat. These can be used in singular and plural forms. Uncountable nouns cannot be counted, such as water.