Use a new situation to check whether the idea travels
Understanding an example does not automatically mean you can use the idea elsewhere. After learning a rule, apply it to a situation with different surface details. A note about arranging a sequence becomes more useful when its principle can guide another sequence, not only the one originally shown.
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Change the setting while keeping the relevant structure
A lesson explains alphabetical order using a list of surnames. Applying the same ordering rule to book titles tests whether the learner can use it beyond the original list.
Transfer means using learning in a different situation. The new situation should still require the same underlying knowledge; changing to an unrelated task does not test the same idea.
A note can include one application that differs in appearance from its main example. Ask what stays the same and what must be adapted.
Transfer is not guaranteed by a clear explanation alone. Practice across relevant variations can help reveal whether the learner understands the principle or has mainly memorised the details of one demonstration.