Mixed Modals Exercises PDFSet 3: Possibility, Deduction & Advice: May, Might, Could, Must & Should Exercises
20 questions·14 min·Answers included·Explanations included
Preview: Questions
Fill in the blank with the correct option.
1.He's been working all day without a break. He ___ be very tired.
a) mustb) mightc) shouldd) could
2.I'm not sure where Lisa is. She ___ be at the library or at home.
a) mustb) mightc) shouldd) can't
3.You've been coughing for a week. You ___ see a doctor soon.
a) mustb) mayc) shouldd) could
4.That ___ be Tom's car. Tom drives a blue Honda, and that one is red.
a) mustn'tb) shouldn'tc) may notd) can't
5.There's someone at the door. It ___ be the delivery man — I ordered a package yesterday.
a) couldb) mustc) shouldd) can't
... and 15 more questions in the PDF
Preview: Answers
1.must
2.might
3.should
4.can't
5.could
... and 15 more answers in the PDF
Preview: Explanations
1."must"(a)
Use 'must' for a strong logical deduction — you are almost certain based on the evidence. Working all day without a break makes it almost certain he is tired. 'Might' or 'could' would express less certainty.
2."might"(b)
Use 'might' to express possibility when you are uncertain. 'I'm not sure' clearly shows the speaker doesn't know, so 'might' (= it's possible) is correct. 'Must' would express certainty, which contradicts 'I'm not sure'.
3."should"(c)
Use 'should' to give advice or recommend an action. A persistent cough warrants medical attention, and the speaker is advising the listener. 'Must' would sound like a command rather than concerned advice.
4."can't"(d)
Use 'can't' for a strong negative deduction — you are almost certain something is NOT true. The car is the wrong colour, so it's logically impossible that it belongs to Tom. 'Mustn't' expresses prohibition, not impossibility. 'May not' would express uncertain possibility.
5."could"(a)
Use 'could' to express a reasonable possibility. The speaker thinks the delivery man is a possible explanation but isn't certain. 'Must' would express near-certainty, which is stronger than the speaker's level of confidence here.
... and 15 more explanations in the PDF
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