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 ReadingNEWStudies Link Bad Sleep to Under-50 Cancer
Two large American studies say that bad sleep may raise the risk of cancer in adults under 50. The studies were shared a…
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 ReadingNEWStudies Link Insomnia to Cancer Risk in Under-50s
Two large American studies have linked chronic poor sleep to a much higher risk of cancer in adults under 50. The findin…
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 ReadingNEWInsomnia Triples Cancer Risk in Under-50s, Studies Find
Two large US studies presented at the American Society of Clinical Oncology (ASCO) annual meeting in Chicago have linked…
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.