21.____b you are familiar with the author's ideas, try reading all the sections as quickly as you possibly can.

　　A) Ever since B) Now that C) So that D) As long as

　　22.The people didn't trust Senator Maxwell , otherwise he ____.

　　A) would have re-elected B) would have been re-elected

　　C) must have been re-elected D) were to be re-elected

　　23.Go straight into the cave and find out what's in there, ____?

　　A) will you

　　B) don't you

　　C) do you

　　D) can you

　　24.The old man was shocked to learn that his illness could result in death if ___D_ untreated.

　　A) to leave

　　B) to be left

　　C) leaving

　　D) left

　　25.Our teacher recommend that we ____ as attentive as possible when we visit the museum.

　　A) are

　　B) be

　　C) were

　　D) shall be

　　2656454656.The old man came upstairs with great strength , his right hand ____ a stick for support.

　　A) held

　　B) holding

　　C) being holding

　　D) was holding

　　27.My wife said in her letter that she would appreciate ____ from you sometime.

　　A) hearing B) to hear C) having heard D) to have heard

　　28.It ____ around nine o'clock when I drove back home because it was already dark.

　　A) had to be B) was to be

　　C) must be D) must have been

　　29.If you act ____ the doctor's advice ,you won't get well again.

　　A) aside from B) contrary to C)capable of D) prior to

　　30.Visitors coming for short periods of time do not always experience ____ intense emotions ____ visitors who live in foreign countries for longer terms.

　　A) the same … as

　　B) both … and

　　C) either... or

　　D) so … that

　　31.Urban mothers had difficulty ____ their children into child care facilities.

　　A) get

　　B) to get

　　C) in getting

　　D) for getting

　　32.If it ____ too much trouble, I'd love a cup of tea.

　　A) isn't

　　B) wasn't

　　C) weren't

　　D) hadn't been

　　33.The population of many Alaskan cities has ____ doubled in the past three years.

　　A)larger than

　　B)as great as

　　C)more than

　　D)as many as

　　34.All that can be done ____.

　　A)have been done

　　B)have done

　　C)has done

　　D)has been done

　　35.A person beating a drum or blowing a trumpet causes vibrations in the air ____ sound waves.

　　A) calls

　　B) called

　　C) is called

　　D) are called