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Home practice · speculation, deduction & mystery vocabulary · answer key included
1 · Speculation & deduction — choose the correct option
Her coat is still on the chair — she ______ far.
The car engine is still warm — someone ______ it in the last hour.
He didn't answer — he ______ his phone in the other room.
The messages were never read — she ______ them.
There ______ a perfectly ordinary reason — there always is.
Nobody heard the door — she ______ very quietly.
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2 · Complete with a word from the mystery bank
- The evidence was strong but entirely drop — no one saw him at the scene.
- That anonymous letter turned out to be a drop — it wasted three weeks of work.
- She had a strong drop that the answer lay closer to home.
- A retired colleague gave them their first fresh drop in six months.
- The internal memo made it clear this was a drop from day one.
- He had a solid drop — he was on a flight, in the air, at the time.
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3 · Rewrite using the modal in brackets
I'm confident she went out. (Rewrite with must have)
It's impossible that he heard the message. (Rewrite with can't have)
There is a strong probability that she took the call inside. (Rewrite with may well have)
It's theoretically possible that he simply forgot. (Rewrite with could have)
I strongly suspect there is a mundane explanation. (Rewrite with there must be)
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4 · Investigative collocations
- to follow a leaddrop or tap here…
- to rule out a suspectdrop or tap here…
- to act on a hunchdrop or tap here…
- to blow the whistle ondrop or tap here…
- to piece something togetherdrop or tap here…
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5 · Voice message · The figure on the path
Listen to a voice message someone leaves a friend after walking home late at night.
📄 Show transcript
Speaker: Hey, it's me. You’re not going to believe what happened last night. I was walking home, you know, from the gym, and it was pretty late, about eleven o'clock. I usually cut through that path behind my building, by the canal, it saves a few minutes. So anyway, I'm walking along, minding my own business, and I see this figure just standing there, kind of in the shadows.
My first thought was, 'Oh, it could have been someone waiting for a friend,' you know? Or, 'It might have been a delivery guy who'd got lost and was checking his phone or something.' But the weird thing was, about twenty minutes later, I realised I’d left my keys at the gym, so I had to go back. And guess what? When I walked past again, the figure was *still there*, in exactly the same spot, in the same hunched-over posture. It hadn't moved an inch!
That’s when I thought, 'It can’t have been either of those things, can it?' I mean, who waits in the same spot for twenty minutes, without moving, just standing there? So creepy! Anyway, I just walked a bit faster. I'm sure it might well have been nothing at all, and there must be a completely boring reason for it, but honestly, it gave me the shivers! I'll tell you all about it properly later. Bye!
- Where and when does the incident happen?
- What two ordinary explanations does he consider?
- What single detail makes him reject both?
- What modal-perfect structures does he use to speculate?
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6 · A short first-person account (170–200 words)
Write a first-person account of a small mystery in your own week — something that almost had an ordinary explanation, but not quite. Use at least four modal perfects and at least four items of mystery vocabulary. End honestly unresolved — do not invent a tidy conclusion.
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