Tom, clean up the broken glass _________ someone walks on it.
How long do you think ______ the computer company brings out a new product?
In the reading room, we found her____ at a desk, with her attention____ on a book.
______ , the players began the game.
— I phoned you yesterday morning. A girl answered, but I didn’t recognize the voice.— Oh, it ____ my younger sister. She was in my room at that moment.
The old woman who______in the deserted house alone for ten years has been settled in a nursing home now.