Find examples Abstract concepts can be hard to understand. It tends to be far easier to form a mental image if you have a concrete example of something. For instance, sour foods usually taste that way because they contain an acid. On its own, that concept might be hard to remember. But if you think about a lemon or vinegar, it’s easier to understand and remember that acids and sour go together. And the examples might help you to identify other food tastes as being due to acids. Indeed, it helps to have at least two examples if you want to apply information to new situations.