I'm sure that David took your books by mistake. David .... have taken your books by mistake.
David must have taken your books by mistake.
You're not allowed to park here. You ......... park here.
You can't / mustn't park here.
I'm sure that Helen feels lonely. Helen..... feel really lonely.
Helen must feel really lonely.
Mary knows how to stand on her head. Mary ... stand on her head.
Mary can stand on her head.
I'm sure they haven't eaten all the food. It's not possible! They .... have eaten all the food.
They can't have eaten all the food.
It was a mistake to park outside the police station. You .... have parked outside the police station.
You shouldn't have parked outside the police station.
Heather possibly hasn't left yet. Heather... not have left yet.
Heather might not have left yet.
It would be a great idea if Harry took a holiday. Harry .... take a holiday.
Harry should take a holiday.
The dentist will see you soon. I don't think he'll be long. / The dentist will see you soon. He ..... be long.
He shouldn't be long.
I'm sure that Brenda isn't over thirty. Brenda..... be over thirty.
Brenda can't be over thirty.
It's possible for anyone to break into this house! Anybody ..... break into this house!
Anybody can / could break into this house!
What would you advise me to do? What do you think I ... do?
What do you think I should do?
I am worrying a lot about my brother. You ... worry. He is fine.
You don't have to / shouldn't worry.
Do I need a different driving licence for a motorbike? Do I ......have a different driving licence for motorbike?
Do I have to have a different driving licence for a motorbike?
Jack is supposed to have arrived half an hour ago. Jack ... have arrived half an hour ago.
Jack should have arrived half an hour ago.
I think it was the cat that took the fish from the table! The cat ..... have taken the fish from the table.
The cat must have taken the fish from the table.