Can he be a good runner? He is so small.
She can’t have finished school.
He can’t be a scientist.
He can’t have been a scientist.
Can she be still sleeping?
Can they have lost the game?
He can’t have said it!
A grown-up man can’t like such books!
She can’t have told you this.
Can it have been so cold?
She can’t have been late for the lesson: she has never been late before.
She can’t have mixed up the streets.
It can’t be true.
Can you have torn my note?
He can’t be in the park now: it is late.
She can’t have written it. I am sure that somebody else has written it.