The Robot Club Announcement
Northbridge Robotics Club has 24 members and one faculty adviser, Mr. Chen. The club will run a mandatory workshop on Saturday in Room 14. The secretary drafted this email to members:
- 'Only students who have submitted the safety form and watched the induction video may use the soldering station.'
- 'If you would have checked the noticeboard, you would have seen the room change.'
- 'Members must not bring guests unless Mr. Chen has approved them in advance, and they must sign in at the door.'
The secretary worries that sentence 1 is ambiguous because 'only' can attach to different parts. The treasurer says sentence 2 sounds wrong. A parent asks whether sentence 3 means guests may sign in themselves. Mr. Chen wants a corrected email that is clear, grammatical, and fair. The club must send it before Friday, and no member may be excluded for a reason the email does not state plainly.
1. Explain the ambiguity in sentence 1. Rewrite it so that the requirement applies to both the safety form and the induction video, and no other reading is possible.
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The problem is scope. In 'Only students who have submitted the safety form and watched the induction video may use the soldering station,' the word 'only' can be read as restricting the group ('only students, not staff or visitors'), restricting the action ('the only thing they may do is use the station'), or restricting the conditions. A reader could also wonder whether 'and' makes both documents necessary or whether either one is enough. The intended rule is that both are necessary conditions for one permission. A clear rewrite is: 'Students may use the soldering station only if they have submitted the safety form and watched the induction video.' Here 'only if' marks both listed conditions as prerequisites, and the modal 'may' grants permission rather than imposing an unrelated duty.
2. Correct sentence 2 and explain the conditional form you use.
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Use the third conditional: 'If you had checked the noticeboard, you would have seen the room change.' The if-clause takes the past perfect ('had checked'), not 'would have checked'. The main clause takes 'would have' plus the past participle ('would have seen'). The sentence describes an unreal past: the listener did not check, so the result did not happen. 'If you would have checked' is a common error because the 'would' from the result is copied into the condition. A useful test is to remove 'if': 'You had checked...' cannot stand alone as the result, so 'would have' belongs only in the main clause.
3. Clarify sentence 3. Who must sign in, and what does 'unless' make conditional? Rewrite the sentence to remove the ambiguity.
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'Unless Mr. Chen has approved them in advance' makes prior approval the condition for bringing guests. The pronoun 'they' is ambiguous: it can refer to 'members' or 'guests'. The parent's reading - that guests may sign themselves in - is possible because 'they' sits closer to 'guests'. The intended rule should state both duties separately: 'Members may bring guests only if Mr. Chen has approved each guest in advance. Guests must sign in at the door.' This uses 'may' for permission, 'must' for the guests' obligation, and 'each guest' to prevent a group approval from being stretched.