Choose one difference worth learning
Do not compare everything at once. Pick the distinction that repeatedly changes the answer: completed versus ongoing situation, stronger versus weaker certainty, neutral versus formal register, premise versus conclusion, or another real boundary. Write it in plain language before opening a quiz.
If the explanation requires a page of exceptions before the learner can make one choice, the contrast may be too broad.
Use new situations, not copied example pairs
After inspecting one clear pair, hide both examples and present a fresh context. Require a choice before feedback. Then explain the decisive feature rather than merely announcing the correct option. Retrieval makes the learner expose the decision they would actually make without an answer key.
A second item should vary vocabulary or topic so success cannot depend on remembering which sentence was on the left side of the page.
Finish by producing both sides of the boundary
Create one sentence where A is natural and another where B is natural. This forces the learner to represent the distinction positively instead of learning one construction as “the wrong one.” If possible, explain in one short sentence what changed between the two contexts.
Metkagram Contrasts and Choices are designed for this workflow: reviewed distinction, bounded decision, immediate explanation and another chance to reuse the Frames.