—Someone is singing next door. Is it Amy?—It ______ be her. She is giving a performance at the theatre now.
It’s very dangerous when you drive your car ______ a certain speed.
Though he is a manager of a big company, he makes ______ a rule to have supper with his family every day.
The letter “u” in the word “______” has a different pronunciation from the others.
If you develop a ______ of talking with others in English, you’ll improve your ability in speaking.
—The Underground Line No. 3 has been in service for about a month. —How exciting ______ news is!