Deduction & Speculation Exercises
Online exercises on modals of deduction and speculation — must be, can't be, could be, might be, and may be — with answers and explanations. Practise modal verbs of probability and certainty for present and past deduction, including past modals of probability such as must have, can't have, and could have + past participle. Multiple choice questions, worksheets, and printable PDF exercises from B1 to B2. 5 exercise sets with 100 questions (B1 - C1 Level).
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Must & Can't: Present Deduction Exercises
Deduction & Speculation Exercises
The Certainty Scale: Must, May, Might, Could & Can't Exercises
Deduction & Speculation Exercises
Speculation About the Present: Must Be, Can't Be & Might Be + -ing Exercises
Deduction & Speculation Exercises
“The office light is on and I can hear typing. Someone ___ in there.”
B1 ReadingNEWParis Fire Empties 900 Homes
A big forest fire has burned about 800 hectares near Paris. The fire is in the Fontainebleau forest, about 60 kilometres…
Past Deduction & Probability: Must Have, Can't Have & Could Have Exercises
Deduction & Speculation Exercises
“The streets are wet this morning. It ___ during the night.”
B2 ReadingNEWFire Near Paris Empties 900 Homes, Arson Suspected
A large wildfire has burned about 800 hectares of the Fontainebleau forest, around 60 kilometres south-east of Paris. Fr…
Advanced Speculation: Must Have Been Doing & Complex Modal Deduction
Deduction & Speculation Exercises
“When I got home at midnight, the kitchen was a mess — flour everywhere, dirty bowls in the sink, and the oven was still warm. Someone ___ all evening.”
C1 ReadingNEWWildfire Near Paris Empties 900 Homes, Arson Suspected
A wildfire of what French officials called "exceptional scale" tore through the Fontainebleau forest about 60 kilometres…
Why practice Deduction & Speculation exercises?
These exercises help you master modals of deduction and speculation in English. Start with must and can't to make strong deductions about the present — drawing logical conclusions from evidence and clues at B1 level. Then learn to use the full certainty scale from must (almost certain) through may, might, and could (possible) to can't (impossible). Next, practise speculating about what is happening right now using must be, can't be, and might be + -ing. Finally, take on advanced past probability and past deduction exercises with must have, can't have, and could have + past participle to draw conclusions about what happened in the past at B2 level.