noun
BAD : The child was caught stealing foods.
GOOD : The child was caught stealing food.
BAD : It is a disgrace to serve such a poor food.
GOOD : It is a disgrace to serve such poor food.
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Food is nearly always uncountable: 'We need to go out and buy some food.' It is countable only when it refers to a particular kind of food: 'baby foods', 'health foods'.