So many people violate traffic regulations that we ____ put too much emphasis on the importance of traffic safety. 

— Must we wear our school uniform this afternoon?— No, you. All of us will go on an outing.

 ---Could you please come to the museum with me this afternoon?---Sorry, I ______ . I have to take a piano lesson at 2 pm.

— You used to 　　　　 the bus to school, didn’t you?— Yes, I did. However, I am used to 　　　　 to school now.

The man ______ be my father. My father is much taller.