1 . To his disappointment, his son became addicted to _______ (surf) the Internet. (所给词的适当形式填空)

2 . Jack denied ________ (steal) the important document of his company. (所给词的适当形式填空)

3 . ________ (expose) to too much violence has a negative impact on the development of children’s character. （所给词的适当形式填空）

4 . My sister is fond of___________(volunteer) in her spare time. (所给词的适当形式填空)

5 . It’s no use ________(cry) over spilt milk. （所给词的适当形式填空）

6 . ________(ignore) the differences between the two research findings will be one of the worst mistakes you make. （所给词的适当形式填空）

7 . I was impressed by the energy and _________(commit) shown by the firefighters. (所给词的适当形式填空)

8 . The elderly are afraid of________(abandon) to the care of strangers.

9 . ________ (expose) to sunlight for too much time will do harm to one’s skin.

10 . The classic books are well worth________ (read) over and over again. （所给词的适当形式填空）