1)Where was Peter yesterday? He … (be) at school. The school year started a week ago.
2)I’m absolutely sure! They … (arrive) yesterday. I saw their tickets.
3)The course … (begin) on the fifth of September but I’m not so certain about it.
4)Are you joking! Nick … (go) to Moscow last week. He’s supposed to be at work now.
5)They … (come from) London, but I’m not sure.
6)We … (take) the wrong turn. We should be there by now.
7)They … (miss) their train. Otherwise they would be here by now.
8)It … (be) Masha who answered the phone because she’s away.
9)I can’t find my cat anywhere. She … (get out) through the window.
The opening is too small.