这个实验原来是中大老师做的……

A well-chosen example does more than illustrate an idea; it shows how that idea behaves under real conditions, where limits, trade-offs, and consequences become visible. In education, effective examples usually move from a familiar situation to a more complex case, helping readers connect abstract principles with decisions they may actually face. For instance, a budgeting lesson becomes more credible when test presents income, rent, irregular expenses, and a modest emergency fund rather than a perfectly tidy set of figures. That practical structure exposes the difference between a plan that works on paper and one that remains resilient when costs rise or priorities change. Editors should also examine whether an example reflects the audience’s circumstances, since a technically accurate scenario may still mislead if it ignores culture, access, scale, or available resources. Good examples therefore function as small models: limited enough to understand quickly, but detailed enough to support sound judgment.