---I think Miss Gao must be in the library. She said she would go there. ---No, she ___________ be there. I have just been there.

My sister met him at the street yesterday afternoon, so he __________ your lecture.

According to the school rules, no student _______ go out of school without the permission of the teachers.

What do you mean, there are only ten tickets? There _________ be twelve. 

You can’t imagine that a well-behaved gentleman __________ be so rude to a lady.