must, can't, might + have done — hedging and deduction
Past deduction for professional updates: what is almost certain, what is impossible, and what is still possible.
Unit 1 hedging vocabulary. You already know may / might / may have from A2–B1. Here we focus on stronger B2 deduction in board updates and emails.
A — Sample sentences
Collocations like there is every likelihood, bound to, cannot take for granted, the odds are, and could well.
1) must have — almost sure it happened
- The launch date slipped — they must have hit a serious bug.
- Downloads are flat; the campaign must have fallen through.
- We must have underestimated how long QA would take.
- The board must have seen the pilot data before they approved funding.
2) can't have / couldn't have — sure it did not happen
- They can't have taken success for granted — the figures prove caution was right.
- We couldn't have sustained momentum without early adopters.
- The team can't have been idle — they were up against it all quarter.
- He couldn't have had no hesitation in saying yes; the risks were obvious.
3) might have / may have / could have — still possible
- The numbers could well look different — we might have misread the trend.
- There is every likelihood they may have delayed the rollout quietly.
- We could have stood a better chance if we had hedged the forecast.
- The odds are we might have lost users during the freeze.
The rest of this lesson is in the General English course:
- B — Quick reference
Try it: Choose the best modal
must have, can't have, or might have?
- The download target was missed — marketing ___ focused on the wrong channel.
(a) must have (b) can't have (c) might have - We ___ taken success for granted; the board warned us repeatedly.
(a) must have (b) can't have (c) might have - The campaign ___ fallen through, but we need to confirm with Sales.
(a) must have (b) can't have (c) might have
Check your answers in the course — it marks them instantly. This is one of the unit's 2 exercises; the other one is in the General English course too.
Practise this unit in the course →