Modals of Speculation about the past / Infinitives

Why were there no buses yesterday? Maybe it was the snow or they _____ been on strike.

• might have

• must have

• couldn't have

You _____ seen her, surely! She was standing right in front of you.

• may have

• might have

• must have

Let's ask at reception to see if they have your keys. Someone _____ found them.

• must have

• might have

• can't have

He _____ gone to Russia. He didn't have a passport.

• must have

• might have

• couldn't have

I explained the homework but she did the wrong page. She _____ misunderstood me.

• must have

• may have

• can't have

She ___ misunderstood my directions. Why else is she late?

• couldn't have

• may have

• must have

I ___ written down the number incorrectly. I've just called a hospital not the restaurant.

• might have

• must have

• may have

Which sentence is NOT a correct sentence?

• Erin may have missed the train.

• Erin must have missed the train.

• Erin can have missed the train.

Which sentence is NOT grammatically correct?

• He can’t have got lost!

• Joseph must have forget about the party.

• I may have left the form at home.

Which sentence CANNOT be used in reply to the sentence below.

‘Oh no! I can’t find my camera! I must have left it in the hotel!’

• ‘Yes, you can have left it in the cupboard by the bed.’

• ‘You can’t have done. We searched the room before we left.’

• ‘You might have left it in the car. Have you looked there?’