Past Modal of Deduction #1

We use must have + past participle when ....

• we aren't sure that something happened

• we are sure something happened

• we think it isn't possible that something happened

• we want to express regret about something that happened

We use may/ might + past participle when ....

• we aren't sure that something happened

• we are sure something happened

• we think it isn't possible that something happened

• we want to express regret about something that happened

We use can't/ couldn't + past participle when ....

• we aren't sure that something happened

• we are sure something happened

• we think it isn't possible that something happened

• we want to express regret about something that happened

John has forgotten about the meeting. We _______ him about it yesterday.

• shouldn't have remind

• should have reminded

• might have reminded

• must have reminded

He _______ a new car. He doesn't have any money.

• must have bought

• can't have bought

• might have bought

• should have bought

I had to wait 45 minutes for a bus yesterday. There _______ an accident or maybe a strike.

• should have been

• must have been

• might have been

• can't have been

She _______ really hard. She passed all her exams with excellent grades.

• might have studied

• can't have studied

• should have studied

• must have studied

I'm sorry but Ms. Devi isn't here. She _______ the office since her table is clean.

• must have already left

• can't have already left

• should have already left

• might have already left

The boss is in a terrible mood. The meeting _______ good.

• can't have been

• must have been

• shouldn't have been

• might have been

The concert was fantastic. You really _______.

• should have come

• should have came

• must have come

• can't have come