37．___________the mountain is, ___________the air is.

A.The high; the thin B.Higher; thinner

C.The higher; the thinner D.The higher; thinner

36. Have you ever___________ that before?

A. heard from B. hear about C. heard of D. hear of

35. The flood couldn't stop the soldiers towards the most dangerous places.

A. from moving B. for moving

C. on moving D. to move

34. You must hand___________ your homework after class.

A. out B. in C. on D. up

33. It's an hour's walk,___________.

A. here and there B. now and then C. up and down D. more or less

32. Not only I but also my mother___________ to plant trees tomorrow.

A. want B. wants C. will want D. are wanting

31. Which of the following is right?

A. Such a difficult work should be given to Tom.

B. Such a difficult job should be finished by Tom.

C. So difficult a work must be done by Tom. D. So difficult a job must give to Tom.

30. Can the museum___________ next year?

A. built B. be built C. build D. will be built

29. Can you tell me___________?

A. where can I put my bike B. where my bike be put

C. where can my bike be put D. where my bike can be put

28.The dog___________ the big tree, or it'll run away and hurt people.

A．has to tie to B．must be tied on C．should tie to D．has to be tied to