Exercises

Past modal verbs of deduction

Exercise 1

1. Nobody knows exactly why he died. But we think it might have been an accident.

We can use might/may have + past participle to talk about something that perhaps happened or was true. We can use can't but not can as a modal verb of deduction. It might have been an accident = Maybe it was an accident.

1. I should have revised more for the exam. I was lazy, and now I'll fail!

We can use should have + past participle to talk about a situation that we expected to happen in the past, but it didn't. We often use this form to express criticism.

1. Sarah looked very happy. She must have passed her driving test.

We can use must have + past participle to say that we are quite sure that something was true or happened in the past. She must have passed her diriving test = I'm sure she passed.

1. I didn't know you were going to Phil's party yesterday. You should have told me!

We can use should have + past participle to talk about a situation that we expected to happen in the past, but it didn’t. We often use this form to express criticism.

1. I can't believe Jim hasn't arrived yet. He must have taken the wrong train.

We can use must have + past participle to say that we are quite sure that something was true or happened in the past. He must have taken the wrong train = I’m sure she took the wrong train.

1. I can't believe Jim hasn't arrived yet. He can't have taken the correct train.

We can use can’t/couldn’t have + past participle to say that we are quite sure that something did NOT happen or was NOT true in the past. He can't have taken the correct train. = I'm quite sure he didn't take the correct train.

1. You couldn't have been ill yesterday. Jessie saw you at the bowling alley.

We can use can’t/couldn’t have + past participle to say that we are quite sure that something did NOT happen or was NOT true in the past. You couldn't have been ill.= I'm quite sure you weren't ill. We can use must but not mustn't as a modal verb of deduction.

1. I don't know where they went but they could have gone to Paris or Marseille.

We can use could/might/may have + past participle to talk about something that perhaps happened or was true. They could have gone to Paris or Marseille.= Perhaps they went Paris or Marseille. We can use can't but not can as a modal verb of deduction.

1. You ought to have paid more attention. Now we are lost.

We can use should/ought to have + past participle to talk about a situation that we expected to happen in the past, but it didn’t. We often use this form to express criticism.

1. The window was broken, so the thieves must have got in through that window.

We can use must have + past participle to say that we are quite sure that something was true or happened in the past. The thieves must have got in through that window. = I'm quite sure the thieves got in through that window.