---Did you notice Tom was busy all day in his office?---Oh, yes, he has just finished his business tour of Chicago. He has a lot of work to ___.
The operation room in every hospital has to ______ bacteria of any kind.
Only ______ a human being.
The president spoke at the business meeting for nearly an hour without ______ his notes.
— Hi, what did our monitor say just now? — Every boy and every girl as well as teachers who are to visit Water Cube ______ asked to be at school gate before 6∶30 tomorrow morning.
You’d better spend your time just on the things you find ______.