According to traffic laws, drivers_____ drive cars after drinking wine.

I’m fond of my sister, but she has a serious shortcoming. She _______ be really stubborn.

You _________ to eat snacks in the classroom.

--- I heard they went skating in the mountains last winter. --- It ______ true because there was little snow there.

--Who’s singing in the next room? Is it Lucy?---It       be her. She has gone to New York.