Choosing the Right Level of Certainty

Study the questions and tasks

Work through the material below, or start the interactive practice above to complete an attempt. Try the exercises before opening any answer or transcript sections, then use them to review your work.

Practice level

B2. Try this level if you can follow the instructions and understand most of the language; choose an earlier level if you need more support.

Question formats

Single choice

How to approach this practice

Read the complete context. Check both the meaning and the grammar, including word forms, collocations and links between sentences.

1. Question 1 · Single choice

   Choose one answer.

   Choose the best completion or reply. The lights are off and the doors are locked. They … gone home.

   1. should to have
   2. must have
   3. must to have
   4. are have
   Check answers and explanations

   Answer

   must have

   Must have plus participle expresses a strong past deduction.

2. Question 2 · Single choice

   Choose one answer.

   Express a possibility without claiming certainty or impossibility: The train has not arrived. It … been delayed, but I am not sure.

   1. must have
   2. cannot have
   3. has
   4. might have
   Check answers and explanations

   Answer

   might have

   Might have expresses an uncertain past possibility.

3. Question 3 · Single choice

   Choose one answer.

   Choose the best completion or reply. That's not Leo's car; his is blue. It … be his.

   1. has
   2. must
   3. ought
   4. can't
   Check answers and explanations

   Answer

   can't

   Can't expresses a confident negative deduction.

4. Question 4 · Single choice

   Choose one answer.

   Express an expectation rather than a requirement or guarantee: The parcel is due today, so it … arrive by evening if all goes well.

   1. should
   2. ought
   3. must
   4. would
   Check answers and explanations

   Answer

   should

   Should expresses a reasonable expectation here.

5. Question 5 · Single choice

   Choose one answer.

   Complete the sentence to say that a reservation we actually made was unnecessary: We … booked; there were plenty of empty tables.

   1. couldn't have
   2. must have
   3. needn't have
   4. had to have
   Check answers and explanations

   Answer

   needn't have

   Needn't have says the completed booking was unnecessary.

6. Question 6 · Single choice

   Choose one answer.

   Choose the best completion or reply. You … have told me earlier; now it's too late to help.

   1. must
   2. ought
   3. should
   4. are
   Check answers and explanations

   Answer

   should

   Should have expresses criticism of a missed earlier action.

7. Question 7 · Single choice

   Choose one answer.

   The meeting was in person, and he was abroad at the time. Express the deduction that his attendance was impossible: He … have been at the meeting.

   1. can't
   2. should
   3. may
   4. must
   Check answers and explanations

   Answer

   can't

   Can't have expresses impossibility based on the stated evidence.

8. Question 8 · Single choice

   Choose one answer.

   Choose the best completion or reply. There's a slight … that the event will be postponed.

   1. possibly
   2. possible
   3. possibility
   4. possibilities
   Check answers and explanations

   Answer

   possibility

   A slight requires the singular noun possibility.

9. Question 9 · Single choice

   Choose one answer.

   Choose the best completion or reply. The results are … to change once more data arrives.

   1. likely
   2. alike
   3. likelihood
   4. liking
   Check answers and explanations

   Answer

   likely

   Likely to introduces a probable future change.

10. Question 10 · Single choice

    Choose one answer.

    Express mere possibility, without stating an expectation: For all we know, she … already be on her way.

    1. must
    2. has
    3. should
    4. may
    Check answers and explanations

    Answer

    may

    May expresses possibility where information is limited.

11. Question 11 · Single choice

    Choose one answer.

    The machines had the same fault and failed at the same moment, making a common cause probable. It is highly … that both failed independently.

    1. unlike
    2. unlikeliest
    3. unlikelihood
    4. unlikely
    Check answers and explanations

    Answer

    unlikely

    Highly modifies the adjective unlikely.

12. Question 12 · Single choice

    Choose one answer.

    Choose the best completion or reply. The team is bound … difficulties at some stage.

    1. to encounter
    2. encounter
    3. encountering
    4. encountered
    Check answers and explanations

    Answer

    to encounter

    Bound to expresses a strong expectation and takes a base verb.

What to review next

Explain why each answer fits the meaning and structure. Record useful phrases and write a new example using each pattern you found difficult.

A focused practice result shows how you did on these tasks. Use several activities across skills to decide what to study next; one practice score does not certify an overall CEFR level.