What              you do if you won in the lottery?

— What are you going to do this weekend?— I don’t know. I ______ visit a friend.

 Jack, look! Everybody is doing homework quietly. ________ you make a noise in class?

---I was told to be here at this time.---Sorry, you ___________. I forgot to tell you we've changed the plan. 

---Look at the boy running on the playground. Is it David? ---It ______ be him. I saw him go to the teachers’ office just now.