Past Modal Verbs

Exercises

Explanation

Basic structure: modal + have + past participle (V3)
Example: She may have forgotten her appointment.

Negative structure: modal + not + have + V3
Example: They might not have read my email.

1. Might have / May have / Could have — past possibility

We use might have, may have, and could have to talk about uncertain past events. These forms express guesses when we do not know the exact truth.

Examples:

• I can’t find my headphones. I might have left them at the gym.

• He isn’t at home. He may have gone out for a walk.

• The lights are off. They could have left already.

• She may not have noticed your message.

• They might not have understood the instructions.

These modal verbs all show possibility, but not certainty.

2. Could have — past ability or opportunity (but didn’t happen)

We use could have to talk about something that was possible in the past, even though the person did not do it.

Examples:

• I could have applied for the scholarship, but I missed the deadline.

• We could have taken the earlier train, but we were too slow.

• He could have finished the task yesterday, but he chose to relax instead.

This form highlights an unrealized opportunity.

3. Must have — strong probability about the past

We use must have when we are almost certain about something that happened in the past. It expresses a logical conclusion based on evidence.

Examples:

• The door was open. Someone must have forgotten to lock it.

• She looks very happy. She must have received good news.

• His shoes are muddy. He must have been in the garden.

This modal shows high confidence.

4. Should have / Ought to have — past advice, criticism, or regret

We use should have or ought to have to say that something was the right or better action in the past, but it did not happen.

Examples:

• You should have checked the map before driving.

• She ought to have replied to the email earlier.

• We should have saved more money last year.

Negative forms

• I shouldn’t have stayed up so late.

• He ought not to have spoken so rudely.

These structures express regret or criticism.

5. Should have / Ought to have — past expectations

We also use these forms when we expected something to happen, but it did not.

Examples:

• The parcel should have arrived yesterday.

• He ought to have been here by now.

This expresses expectation, not advice.

6. Continuous forms — actions happening at a specific past moment

To talk about actions that were in progress at a moment in the past, we use:

modal + have been + -ing

Examples:

• When I called, they must have been studying.

• She might have been cooking when the power went out.

• He could have been driving home around that time.

This structure shows ongoing past activity.

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