Generally, we use the plural for categories but some of them are in singular. We don't put the plural form when it has a different meaning. For example Beef and Beefs. We are talking of the meat and not the animal, so there is no "s".
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Generally, we use the plural for categories but some of them are in singular. We don't put the plural form when it has a different meaning. For example Beef and Beefs. We are talking of the meat and not the animal, so there is no "s". But "Rillettes" in french (and others languages) doesn't have a singular form.
Sometimes plural or singular depends on the language.
Sometimes plural or singular depends on the language.