MEANING
That fish can't be cooked yet. It's only been under the grill for two minutes.
I'm sure it isn't true; Present
I'm sure you are joking.
You must be joking.
Even the cat didn't eat the fish. It ___ (be) bad.
Even the cat didn't eat the fish. It must have been bad.
This meat is a bit dry and chewy. The chef must have overcooked it.
I'm sure it is true; Past
It's possible that he'll give you a ring this evening.
He might give you a ring this evening.
His breath smells awful. He _____ (eat) a lot of garlic last night.
His breath smells awful. He must have eaten a lot of garlic last night.
There were three tins of olives in the cupboard. We can't have eaten them all, can we?
I'm sure it isn't true; Past
I'm sure Patricia isn't wearing her scarf. I saw it hanging on the hook on the back door.
Patricia can't be wearing her scarf. I saw it hanging on the hook on the back door.
Beer _____ (invent) in Iran about 7000 years ago, but nobody's quite sure.
Beer might have been invented in Iran about 7000 years ago, but nobody's quite sure.
Don't take the chicken out of the freezer yet. We might be eating out tonight if I can book a table.
It's possibly true; Present
I'm certain that James has got my mobile.
James must have my mobile. I let him use it to call his sister this morning.
"Where are my keys?" "You _____ (leave) them in the restaurant, or possibly in the car."
"Where are my keys?" "You might have left them in the restaurant, or possibly in the car."
You haven't eaten a thing since yesterday lunchtime. You must be starving.
I'm sure it's true; Present
I'm sure that isn't Jim over there. His hair isn't as long as that.
That can't be Jim over there. His hair isn't as long as that.
What a fantastic dip! You _____ (spend) ages preparing this food.
What a fantastic dip! You must have spent ages preparing this food.