The experiment shows that proper amounts of exercise, if ________ regularly, can improve our health.

A. being carried out          B. carrying out                 C. carried out           D. to carry out

 The course ________ for introducing America is very popular with students this term.

A. is intended             B. intending           C. having intended    D. intended

 Finding information in today’s world is easy, but the ________ is how you can tell whether the information you get is useful or not.

A. conclusion                   B. challenge          C. conflict               D. possibility

 It was too noisy outside. Not until ________ at the top of my voice ________ his head.

A. I shouted; did he turn                              B. I shouted; had he turned

C. did I shout; did he turn                             D. had I shouted; he turned

 — How often do you see President?

— It varies ________ what I’m working on. Maybe a few times a month.

A. depends on                    B. depended on          C. depending on               D. depend on

 Be careful not to ________ any letter when you spell the word.

A. leave off　　           B. leave out　　　    C. pick out　               D. take off

 ________ from the top of the tower, the south foot of the mountain is a sea of trees.

A. Seen                     B. Seeing                C. Having seen        D. To see

 — Shall I turn on the TV, Mom?

   — No. You should be quiet ________ wake up your sleeping brother.

A. so not as to                   B. so as not to            C. so as to not                 D. not so as to

 The manager ________ one of the hotel servants of stealing the money.

A. charged                        B. complained         C. blamed                        D. accused

 It is you rather than your wife, ________ to blame for your son’s bad behavior at school.

A. that is                     B. who is                    C. that should                D. who are