Resolving a Two-Key Conditional and Reported-Speech Item
You are finalising two 1-mark grammar items. Item 14: 'If the bus ___ (not arrive) by eight, we ___ (walk) to school.' Provisional key: 'did not arrive / would walk'. A teacher objects that 'does not arrive / will walk' is also correct. Item 15: 'The librarian said, "You must return the book tomorrow."' A student writes: 'The librarian said that we must return the book the next day.' Provisional key accepts only 'had to return'. The instructions say each item must have one defensible answer, test the intended grammar point, and not penalise a correct alternative. You have authority to change the key or rewrite the stem, but not to delete either item. Both items are worth one mark and will appear in the final paper.
1. Decide Item 14: change the key, rewrite the stem, or keep it. Justify your decision.
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Both versions are grammatical, but they mean different things. 'Does not arrive / will walk' is a real future condition: we have a plan. 'Did not arrive / would walk' is a hypothetical or habitual-past condition: we are imagining a case. Without context, the item has two keys, so the provisional key is unfair. The best fix is not to delete the item but to rewrite the stem to supply the intended meaning: 'We have checked the timetable. If the bus ___ (not arrive) by eight, we ___ (walk) to school.' Key: 'does not arrive / will walk'. If the examiner wants the hypothetical, write: 'We missed the bus. If it ___ (not arrive) by eight, we ___ (walk).' Key: 'did not arrive / would walk'. Context, not the blank, decides.
2. Decide Item 15: is the student's answer defensible, and what key do you adopt?
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The student's answer is defensible. In reported speech, 'must' can remain when the obligation is still current or when the reporter presents it as ongoing; 'had to' is the backshifted form and is also correct. The provisional key penalises a correct alternative. Because the brief forbids that, adopt both answers or rewrite the stem to force one. To force 'had to', add a past-time frame: 'The librarian said this last week, and the deadline has now passed.' Then the obligation is reported as past and 'had to return' is the natural key. If the stem stays as it is, accept both.
3. Which item is less suitable for a single-mark objective test, and what general rule follows?
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Item 15 as written is the less suitable of the two for a single-mark objective test, because modality in reported speech depends on whether the obligation is still live. Item 14 becomes suitable once context is supplied. The general rule: do not test a form whose correctness depends on unstated context; either state the context or accept the defensible alternatives. In a 1-mark item, ambiguity is a key error, not a difficulty feature.