Mrs. White showed her students some old maps          from the library

The harder we study, the more questions we think of        .

The witnesses_________ by the police just now described the fight quite differently.

A student at a Nevada middle school opened fire on campus, wounding two l2-year-old boys    and__________ a math teacher.

During the examination we are required to stay in our seats, keep our eyes on our work, ____ to  anyone.

Miss Sullivan clarified the science Project in Simple but vivid language so as to make it easier for teenagers ________.

It’s dangerous if you have the fire _____ all night long.

Principal White has been working in the school for about 20 years, ____all his energy to teaching and researching as well as the running of a healthy school.

---What do you think of his talk on Information Technology? 
---Oh, excellent. It's worth ________．

______ to computer games, the boy began to dislike school, which made his parents worried.