---Someone is knocking at the door. Is it your brother?---No, it        be him. He’s gone to Hunan.

You should _____ some English every day. It’s good for your vocabulary.

“Mary looks hot and dry.” “So _____ you if you had so high a fever.”

When we were young, every evening my brother and I ______ stay at home waiting for our mother.

－ Whose is this blue bike? －It ________ be Mary’s. Her bike is black and white.