Look! The man at the gate ____ be our headmaster. He is always standing there every morning.– No, it _____ be him. He is holding a meeting in the office now.

I’m considering________to Qingdao for my holiday by train.-Why not try________by ship for a change?[ ]

It’s good manners to be ________ while watching the raising of our national flag.

The movie theater is the best place _____on weekends.

John is ________ honest boy. He has ________ useful book.