Degrees of certainty

Our car broke down and we couldn't \ may not have enough money to pay for the repairs.

They might\can't\should have gone home. I don't see him anywhere.

You have to\ should be joking. He can't have \ might not have passed away. I saw him on TV just now.

They're going whitewater rafting. They have to\ may be mad to do such a thing!

He didn't answer the phone. He can't have been sleeping\must have been sleeping.

She couldn't \ might not want to come with us.

Many accidents could\ must\ can be prevented with a little care.

I don't know where Bernard is - he must\could be playing tennis with Carrie.

Her new car looks expensive. It must hace cost\ mus cost\ can't have cost a fortune.

The road is wet. It can't have been raining\must be raining\must have been raining.

She is down in the dumps. She must\ can't \ may have broken up with her partner.

Mr. Morris must \ can't be nearly years old but he doesn't look it.

Surely he mustn't\can't still be alive after all this time.

You can't be hungry\must be hungry\ should be hungry. You've only just had lunch.