Countable and uncountable nouns seem even trickier at the more advanced levels. That’s when students encounter a good number of words that have both meanings. Take truth, for example. We often use it abstractly, but it’s possible to talk about the truths that are self-evident, right?
The best thing to hold on to is a set of guidelines. We can remind students that uncountable nouns are generally abstract. If a noun can have both meanings, then the more specific the meaning is, then the more likely it is be to countable: a lot of debt vs. pay off all my debts, the smell of bread vs. a bakery selling different breads, etc.
A good resource like Next Generation Grammar 3 will provide additional guidance through reference charts that categorize uncountable nouns. Students can learn that types of sports, activities, liquids, and occupations are some examples of uncountable nouns.
For some practice on this topic, check out my What You Can Count On_handout.