Having checked the doors were closed, and ___ all the lights were off, the boy opened the door to his bedroom.
_____ for making so many mistakes in the exam, she was in low spirits.
Listen to the two girls by the window. What language ________?
— Isn’t that Ann’s husband over there? — No, it ________ be him — I’m sure he doesn’t wear glasses.
______ disappointed us most was that the guide was always asking us to leave ____ we thought very interesting.
The teacher couldn’t make himself ____ attention to because students were addicted to the short message.