20.He was in hospital for six months. He felt as if he was ___ from the outside world.

A. cut down　　 B. cut off　　　 C. cut up　　 D. cut in

19. Visitors can go on exciting rides ___ they can feel what it is like to do the things they have seen their heroes 　　　in the movie.

A. where; to do　　 　　　B. where; do　　　　

C. which; doing　　　　　 D. that; do

18.He tried to go away without being noticed by the teacher ,but luck ___ him.

A. went with　　　 B. went along　　 C. went against　　 D. went over

17. 　　　　　in the regulations that you should not tell others the password of your email account.

A. What is required　　 B. What requires　　

C. It is required　　　　 D. It requires